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1.
Clin Orthop Surg ; 16(2): 322-325, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38562628

RESUMEN

Background: Toe symphalangism is characterized by a fusion of the interphalangeal joint between the middle and distal phalanges. While typical lesser toe fractures heal well with conservative treatment, in our clinical experience, we encountered patients with symphalangeal toe fractures who experienced long-lasting pain and delayed radiographic union. Therefore, this study aimed to report radiographic outcomes following conservative treatment of symphalangeal fractures of the lesser toes. Methods: We retrospectively reviewed 14 patients with symphalangeal lesser toe fractures who were treated conservatively. We investigated the mechanism of injury and measured the time from the initial injury date to the complete radiographic union. The fracture gap distance was measured on an initial lateral radiograph. Results: Symphalangeal fractures involved the fourth toe in 4 patients (28.5%) and the fifth toe in 10 patients (71.4%). Regarding the mechanism of injury, 6 patients (42.9%) were injured by stubbing or bumping into the door, 5 patients (35.7%) were injured by tripping, 2 patients (14.3%) were injured by heavy objects falling directly on their toes, and 1 patient (2.3%) complained of pain after wearing pointed shoes for half a day. The mean time to complete union was 9.1 months, and the median period was 5.5 months (range, 0.8-29 months). The initial gap of the fracture was 0.60 mm (range, 0.30-1.04 mm). Conclusions: The results of our case series may help counsel patients in the outpatient clinic that prolonged healing time may be required for the union of symphalangeal toe fractures.


Asunto(s)
Traumatismos del Tobillo , Fracturas Óseas , Traumatismos de la Rodilla , Humanos , Tratamiento Conservador , Estudios Retrospectivos , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/terapia , Dedos del Pie/lesiones , Dolor , Resultado del Tratamiento
2.
Heliyon ; 10(6): e27310, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38509976

RESUMEN

Since the introduction of transcatheter aortic valve (AV) implantation as a viable option, surgical bioprosthetic AVs have recently started incorporating shorter struts considering future valve-in-valve procedures. However, the effect of leaflet coaptation geometry on the longevity of these valves remains unexplored. To address this gap, we performed a finite element analysis on bioprosthetic AVs with varying strut heights using a two-way fluid-structure interaction method. To establish a baseline, we used a standard height based on a rendered platform image of the CE PERIMOUNT Magna Ease valve from Edward Lifesciences in Irvine, CA. Bovine pericardium properties were assigned to the leaflets, while normal saline properties were used as the recirculating fluid in hemodynamic simulations. The physiological pressure profile of the cardiac cycle was applied between the aorta and left ventricle. We calculated blood flow velocity, effective orifice area (EOA), and mechanical stress on the leaflets. The results reveal that as the strut height increases, the stroke volume increases, leakage volume decreases, and EOA improves. Additionally, the maximum mechanical stress experienced by the leaflet decreases by 62% as the strut height increases to 1.2 times the standard height. This research highlights that a low-strut design in bioprosthetic AVs may negatively affect their durability, which can be useful in design of next-generation bioprosthetic AVs.

3.
Pharmaceutics ; 16(2)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38399300

RESUMEN

We performed this study to evaluate whether saturated fatty acid (SFA) emulsions affect the BBB and determine the duration of BBB opening, thereby promoting drug delivery to the brain. Butyric, valeric, caproic, enanthic, and caprylic acid emulsions were infused into the carotid artery of the rat model. We evaluated the BBB opening and drug delivery over time. The trypan blue and doxorubicin delivery studies were repeated from 30 min to 6 h. In the 1 h rats in each group, transmission electron microscopy (TEM) was performed to morphologically evaluate tight junctions, and the delivery of temozolomide was assessed by desorption electrospray ionization mass spectrometry. The ipsilateral hemisphere was positive for trypan blue staining in all the five SFA emulsion groups. In the valeric, enanthic, and caprylic acid emulsion groups, RGB ratios were significantly higher at 30 min and decreased thereafter. Doxorubicin delivery increased in all emulsion groups at all time points. Tight junctions were observed to be open in all groups. TMZ delivery was significantly higher in the ipsilateral hemisphere. In conclusion, intra-arterially infused SFA emulsions opened the BBB and promoted drug delivery within 30 min, which decreased thereafter. Therefore, SFA emulsions may aid BBB research and promote drug delivery to the brain.

4.
Cerebrovasc Dis ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38412839

RESUMEN

Introduction Stroke lesion volume on MRI or CT provides objective evidence of tissue injury as a consequence of ischemic stroke. Measurement of "final" lesion volume at 24hr following endovascular therapy (post-EVT) has been used in multiple studies as a surrogate for clinical outcome. However, despite successful recanalization, a significant proportion of patients do not experience favorable clinical outcome. The goals of this study were to quantify lesion growth during the first week after treatment, identify early predictors, and explore the association with clinical outcome. Methods This is a prospective study of stroke patients at two centers who met the following criteria: i) anterior large vessel occlusion (LVO) acute ischemic stroke, ii) attempted EVT, and iii) had 3T MRI post-EVT at 24hr and 5-day. We defined "Early" and "Late" lesion growth as ≥10mL lesion growth between baseline and 24hr DWI, and between 24hr DWI and 5-day FLAIR, respectively. Complete reperfusion was defined as >90% reduction of the volume of tissue with perfusion delay (Tmax>6sec) between pre-EVT and 24hr post-EVT. Favorable clinical outcome was defined as modified Rankin scale (mRS) of 0-2 at 30 or 90 days. Results One hundred twelve patients met study criteria with median age 67 years, 56% female, median admit NIHSS 19, 54% received IV or IA thrombolysis, 66% with M1 occlusion, and median baseline DWI volume 21.2mL. Successful recanalization was achieved in 87% and 68% had complete reperfusion, with an overall favorable clinical outcome rate of 53%. Nearly two thirds (65%) of the patients did not have Late lesion growth with a median volume change of -0.3mL between 24hr and 5-days and an associated high rate of favorable clinical outcome (64%). However, ~1/3 of patients (35%) did have significant Late lesion growth despite successful recanalization (87%: 46% mTICI 2b/ 41% mTICI 3). Late lesion growth patients had a 27.4mL change in Late lesion volume and 30.1mL change in Early lesion volume. These patients had an increased hemorrhagic transformation rate of 68% with only 1 in 3 patients having favorable clinical outcome. Late lesion growth was independently associated with incomplete reperfusion, hemorrhagic transformation, and unfavorable outcome. Conclusion Approximately 1 out of 3 patients had Late lesion growth following EVT, with a favorable clinical outcome occurring in only 1 out of 3 of these patients. Most patients with no Early lesion growth had no Late lesion growth. Identification of patients with Late lesion growth could be critical to guide clinical management and inform prognosis post-EVT. Additionally, it can serve as an imaging biomarker for the development of adjunctive therapies to mitigate reperfusion injury.

5.
Neurosurgery ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376157

RESUMEN

BACKGROUND AND OBJECTIVES: Severe traumatic brain injury (sTBI) represents a diffuse, heterogeneous disease where therapeutic targets for optimizing clinical outcome remain unclear. Mean pressure reactivity index (PRx) values have demonstrated associations with clinical outcome in sTBI. However, the retrospective derivation of a mean value diminishes its bedside significance. We evaluated PRx temporal profiles for patients with sTBI and identified time thresholds suggesting optimal neuroprognostication. METHODS: Patients with sTBI and continuous bolt intracranial pressure monitoring were identified. Outcomes were dichotomized by disposition status ("good outcome" was denoted by home and acute rehabilitation). PRx values were obtained every minute by taking moving correlation coefficients of intracranial pressures and mean arterial pressures. Average PRx trajectories for good and poor outcome groups were calculated by extending the last daily averaged PRx value to day 18. Each patient also had smoothed PRx trajectories that were used to generate "candidate features." These "candidate features" included daily average PRx's, cumulative first-order changes in PRx and cumulative second-order changes in PRx. Changes in sensitivity over time for predicting poor outcome was then evaluated by generating penalized logistic regression models that were derived from the "candidate features" and maximized specificity. RESULTS: Among 33 patients with sTBI, 18 patients achieved good outcome and 15 patients had poor outcome. Average PRx trajectories for the good and poor outcome groups started on day 6 and consistently diverged at day 9. When targeting a specificity >83.3%, an 85% maximum sensitivity for determining poor outcome was achieved at hospital day 6. Subsequent days of PRx monitoring showed diminishing sensitivities. CONCLUSION: Our findings suggest that in a population of sTBI, PRx sensitivities for predicting poor outcome was maximized at hospital day 6. Additional study is warranted to validate this model in larger populations.

6.
Curr Issues Mol Biol ; 46(1): 513-526, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38248335

RESUMEN

The process of skin aging is intricate, involving intrinsic aging, influenced by internal factors, and extrinsic aging, mainly caused by exposure to UV radiation, resulting in photoaging. Photoaging manifests as skin issues such as wrinkles and discoloration. The skin microbiome, a diverse community of microorganisms on the skin's surface, plays a crucial role in skin protection and can be affected by factors like humidity and pH. Probiotics, beneficial microorganisms, have been investigated for their potential to enhance skin health by regulating the skin microbiome. This can be accomplished through oral probiotics, impacting the gut-skin axis, or topical applications introducing live bacteria to the skin. Probiotics mitigate oxidative stress, suppress inflammation, and maintain the skin's extracellular matrix, ultimately averting skin aging. However, research on probiotics derived from human skin is limited, and there is no established product for preventing photoaging. The mechanism by which probiotics shield the skin microbiome and skin layers from UV radiation remains unclear. Recently, researchers have discovered Lactobacillus in the skin, with reports indicating a decrease in this microorganism with age. In a recent study, scientists isolated Lactobacillus iners KOLBM20 from the skin of individuals in their twenties and confirmed its effectiveness. A comparative analysis of genetic sequences revealed that strain KOLBM20 belongs to the Lactobacillus genus and closely relates to L. iners DSM13335(T) with a 99.20% similarity. Importantly, Lactobacillus iners KOLBM20 displayed anti-wrinkle properties by inhibiting MMP-1. This investigation demonstrated the inhibitory effect of KOLBM20 strain lysate on MMP-1 expression. Moreover, the data suggest that KOLBM20 strain lysate may prevent UVB-induced MMP-1 expression by inhibiting the activation of the ERK, JNK, and p38 signaling pathways induced by UVB. Consequently, KOLBM20 strain lysate holds promise as a potential therapeutic agent for preventing and treating skin photoaging.

7.
ACS Appl Mater Interfaces ; 16(3): 4013-4023, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38189267

RESUMEN

Electrical anisotropy, which is characterized by the efficient transmission of electrical signals in specific directions, is prevalent in both natural and engineered systems. However, traditional anisotropically conductive materials are often rigid and dry, thus limiting their utility in applications aiming for the seamless integration of various technologies with biological tissues. In the present study, we introduce a method for precisely controlling the microstructures of conductive and insulating polymers to create highly anisotropically conductive composite hydrogels. Our methodology involves combining aligned poly(vinyl alcohol) microfibrils, infused poly(3,4-ethylenedioxythiophene) polystyrenesulfonate, and sodium citrate precipitation to form dense, aligned conductive paths. This significantly enhances the electrical conductivity anisotropy (σ∥/σ⊥ ≈ 60.8) within these composite hydrogels.

8.
Adv Sci (Weinh) ; 10(35): e2303728, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37840396

RESUMEN

Intuitive and perceptual neuroprosthetic systems require a high degree of neural control and a variety of sensory feedback, but reliable neural interfaces for long-term use that maintain their functionality are limited. Here, a novel hybrid bionic interface is presented, fabricated by integrating a biological interface (regenerative peripheral nerve interface (RPNI)) and a peripheral neural interface to enhance the neural interface performance between a nerve and bionic limbs. This interface utilizes a shape memory polymer buckle that can be easily implanted on a severed nerve and make contact with both the nerve and the muscle graft after RPNI formation. It is demonstrated that this interface can simultaneously record different signal information via the RPNI and the nerve, as well as stimulate them separately, inducing different responses. Furthermore, it is shown that this interface can record naturally evoked signals from a walking rabbit and use them to control a robotic leg. The long-term functionality and biocompatibility of this interface in rabbits are evaluated for up to 29 weeks, confirming its promising potential for enhancing prosthetic control.


Asunto(s)
Biónica , Nervios Periféricos , Animales , Conejos , Electromiografía , Nervios Periféricos/fisiología , Prótesis e Implantes , Regeneración Nerviosa/fisiología
9.
Environ Pollut ; 338: 122721, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37838319

RESUMEN

Currently, severe environmental issues have led to a great transition in the automotive industry from internal combustion engine vehicles to electric vehicles, but this transition will take time more than 10 years, which still requires the use of internal combustion engine vehicles. However, these vehicles emit a significant amount of hydrocarbons, in addition to nitrogen oxides (NOx), due to incomplete fuel combustion. They contribute to the formation of photochemical smog when they react with NOx in the presence of sunlight. To effectively remove these hydrocarbons from the exhaust gas of turbo-gasoline engines or diesel engines, we investigated the abatement of propane and iso-pentane, two typical hydrocarbons. In particular, we studied commercial Pd catalysts and revealed how the Pd loading and aging process simulating 4k and 100k mileage affected hydrocarbon abatement abilities, and their phases were identified using characterization technique, including CO chemisorption, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HR-TEM). We also suggested the reaction pathway for the complete oxidation of propane over Pd catalyst based on the reaction orders of propane and oxygen: Propane adsorbs on O atoms of PdO, and the kinetically relevant C-H bond cleavage step occurs by the interaction with abundant neighboring O atoms of PdO. Finally, the propane and iso-pentane abatement ability of the Pd catalyst aged for 100k mileage were evaluated under realistic exhaust gas conditions, and the effect of each gas component in the realistic exhaust gas was identified; water inhibits the catalytic reaction of hydrocarbons by occupying the active sites, whereas NO catalyzes the hydrocarbon oxidation reaction by either changing the reaction pathway or active sites under fuel-lean conditions. These findings enable us to effectively reduce environmental pollution and facilitate a smoother transition from internal combustion engine vehicles to electric vehicles.


Asunto(s)
Pentanos , Esmog , Propano , Hidrocarburos/análisis , Emisiones de Vehículos/análisis , Gasolina/análisis
10.
J Orthop Surg Res ; 18(1): 615, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608307

RESUMEN

BACKGROUND: The minipig has been used for research in various fields of medicine, even in orthopedics. Though previous studies have already suggested other methods to create osteoporotic bone, those methods had some disadvantages for taking time and efforts. Therefore, we aimed to generate osteoporotic proximal humerus and proximal femur of minipig using EDTA solution and validate their properties through dual energy X-ray absorptiometry (DEXA), micro-CT study, histological and biomechanical ways. METHODS: Six minipigs were used. Out of a total of 12 proximal humerus (PH) and 12 proximal femurs (PF), 6 PH and 6 PF were used as the decalcified group and the opposite side as the non-decalcified group. In vitro decalcification with Ca-chelating agents (0.5 M EDTA solution, pH 7.4) was used. Area BMD (aBMD) was measured using DEXA, Volumetric BMD (vBMD), and microstructure were measured using micro-CT. Universal testing machine was used to measure ultimate load to failure (ULTF). Each group was compared using two types of suture anchors (all-suture anchor, ASA, and conventional screw type anchor, CA). RESULTS: There was a significant difference in aBMD and cortical thickness (aBMD: decalcified, 0.433 ± 0.073 g/cm2, undecalcified, 0.962 ± 0.123 g/cm2, p < 0.001; cortical thickness: decalcified, 0.33 ± 0.34 mm, undecalcified, 1.61 ± 0.45 mm, p < 0.001). In the case of ASA, the ULTF was significantly lower in the decalcified group (decalcified: 176.6 ± 74.2 N, non-decalcified: 307.7 ± 116.5 N, p = 0.003). In the case of CA, there was no significant difference (decalcified: 265.1 ± 96.0 N, undecalcified: 289.4 ± 114.5 N, p = 0.578). CONCLUSION: We demonstrated that decalcification with EDTA solution significantly decreased aBMD, vBMD, and cortical thickness. Decalcified minipig bone using EDTA resulted in similar biomechanical properties as osteoporotic human bone with respect to anchor pull-out.


Asunto(s)
Fémur , Osteoporosis , Animales , Ácido Edético , Fémur/diagnóstico por imagen , Húmero/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Porcinos , Porcinos Enanos
11.
J Neuroimaging ; 33(5): 725-730, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37291461

RESUMEN

BACKGROUND AND PURPOSE: Elevated mean flow velocity (MFV) on transcranial Doppler (TCD) is used to predict vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Hyperemia should be considered when observing elevated MFV. Lindegaard ratio (LR) is commonly used but does not enhance predictive values. We introduce a new marker, the hyperemia index (HI), calculated as bilateral extracranial internal carotid artery MFV divided by initial flow velocity. METHODS: We evaluated SAH patients hospitalized ≥7 days between December 1, 2016 and June 30, 2022. We excluded patients with nonaneurysmal SAH, inadequate TCD windows, and baseline TCD obtained after 96 hours from onset. Logistic regression was conducted to assess the significant associations of HI, LR, and maximal MFV with vasospasm and delayed cerebral ischemia (DCI). Receiver operating characteristic analyses were employed to find the optimal cutoff value for HI. RESULTS: Lower HI (odds ratio [OR] 0.10, 95% confidence interval [CI] 0.01-0.68), higher MFV (OR 1.03, 95% CI 1.01-1.05), and LR (OR 2.02, 95% CI 1.44-2.85) were associated with vasospasm and DCI. Area under the curve (AUC) for predicting vasospasm was 0.70 (95% CI 0.58-0.82) for HI, 0.87 (95% CI 0.81-0.94) for maximal MFV, and 0.87 (95% CI 0.79-0.94) for LR. The optimal cutoff value for HI was 1.2. Combining HI <1.2 with MFV improved positive predictive value without altering the AUC value. CONCLUSIONS: Lower HI was associated with a higher likelihood of vasospasm and DCI. HI <1.2 may serve as a useful TCD parameter to indicate vasospasm and DCI when elevated MFV is observed, or when transtemporal windows are inadequate.


Asunto(s)
Isquemia Encefálica , Hiperemia , Hemorragia Subaracnoidea , Vasoespasmo Intracraneal , Humanos , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/diagnóstico por imagen , Hiperemia/diagnóstico por imagen , Hiperemia/complicaciones , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiología , Isquemia Encefálica/etiología , Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Ultrasonografía Doppler Transcraneal/métodos
12.
Brain Behav ; 13(6): e2994, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37218399

RESUMEN

AIMS: To determine whether the blood-brain barrier (BBB) opens to enhance drug delivery during the acute stage of unsaturated fat embolism. METHODS: We infused oleic, linoleic, and linolenic acid emulsions through the right common carotid artery of rats, followed by trypan blue for gross and lanthanum for electron microscopic (EM) examination. Doxorubicin and temozolomide were also administered, and then the rats were euthanized at 30 min, 1 h, and 2 h. Trypan blue hue was analyzed to semiquantitatively measure BBB opening. Desorption electrospray ionization-mass spectrometry (DESI-MS) imaging was used to evaluate drug delivery. RESULTS: Trypan blue staining observed in each group 30 min after emulsion infusion increased at 1 h and decreased after 2 h in the oleic acid group. The linoleic and linolenic acid groups showed weak staining over time. The hue and trypan blue analysis results were corroborative. EM showed tight junction opening, whereas DESI-MS imaging showed increased doxorubicin and temozolomide signal intensities in ipsilateral hemispheres of all three groups. CONCLUSION: We demonstrated that oleic, linoleic, and linolenic acid emulsions opened the BBB, promoting drug delivery to the brain. Hue analysis and DESI-MS imaging are appropriate for analysis of doxorubicin and temozolomide concentrations in brain tissue.


Asunto(s)
Ácidos Grasos no Esterificados , Ácido alfa-Linolénico , Ratas , Animales , Emulsiones , Temozolomida , Azul de Tripano , Encéfalo , Arterias Carótidas , Arteria Carótida Común , Doxorrubicina/farmacología
13.
J Korean Med Sci ; 38(18): e137, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37158773

RESUMEN

BACKGROUND: The purpose of this study was to investigate the change in the incidence rate, length of hospital stay (LOS), in-hospital mortality rate, and surgical method of hip fractures during the coronavirus disease 2019 (COVID-19) pandemic in South Korea where lockdown restrictions were not implemented. METHODS: We calculated the expected values of the incidence of hip fractures, in-hospital mortality and LOS of hip fracture patients in 2020 (COVID period) based hip fracture database of the Korean National Health Insurance Review and Assessment (HIRA) during a 9-year period from 2011 to 2019 (pre-COVID period). A generalized estimating equation model with Poisson distribution and logarithmic link function was used to estimate adjusted annual percent change (PC) of incidence rate and 95% confidence intervals (CIs). Then, we compared the annual incidence, in-hospital mortality rate and LOS in 2020 with the expected values. RESULTS: The overall incidence rate of hip fracture in 2020 was not significantly different from the expected value (PC, -5%; 95% CI, -13 to 4; P = 0.280). In women, the incidence rate of hip fracture in age groups over 70 years was smaller than the predicted value (P < 0.001). The in-hospital mortality rate was not significantly different from the expected value (PC, 5%; 95% CI, -8 to 19; P = 0.461). The mean LOS was larger than the expected value by 2% (PC, 2%; 95% CI, 1 to 3; P < 0.001). In intertrochanteric fracture, the proportion of internal fixation was smaller than the predicted value by 2% (PC, -2%; 95% CI, -3 to -1; P < 0.001), and that of hemiarthroplasty was larger than the predicted value by 8% (PC, 8%; 95% CI, 4 to 14; P < 0.001). CONCLUSIONS: In 2020, the incidence rate of hip fracture did not significantly decrease, and in-hospital mortality rate did not significantly increase compared to the expected rates, which were projected based on the HIRA hip fracture data from 2011 to 2019. Only LOS increased slightly.


Asunto(s)
COVID-19 , Fracturas de Cadera , Humanos , Femenino , Anciano , Análisis de Series de Tiempo Interrumpido , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Fracturas de Cadera/epidemiología , República de Corea/epidemiología
14.
J Korean Soc Radiol ; 84(2): 441-453, 2023 Mar.
Artículo en Coreano | MEDLINE | ID: mdl-37051399

RESUMEN

Purpose: To evaluate the development, location, and volume of a VX2 carcinoma using four inoculation methods in a rabbit brain. Materials and Methods: Inoculation of a VX2 cell suspension was performed 1) on the appointed day, 2) seven days after storing a VX2 carcinoma in a freezer or 3) seven days after storing a VX2 carcinoma in a deep freezer after sacrificing the donor rabbits. 4) Without sacrificing the rabbits, the VX2 cell suspension was obtained using a gun biopsy, inoculation was performed on the appointed day. MR imaging was performed 10 days after inoculation. Brain tissues were obtained the day after. The development, location, and volume of the tumor were evaluated. Results: Seventeen of the 18 rabbits inoculated on the appointed day developed tumors (average tumor volume, 106.32 mm3). One of five inoculated seven days after storing the VX2 tumor in the freezer, and three of five inoculated seven days after storing the VX2 tumor in the deep freezer developed tumors. Inoculation with a VX2 cell suspension obtained with a gun biopsy from five rabbits revealed development of tumors in only two rabbits. The tumors mostly developed in the superficial cortex. Conclusion: TVX2 rabbit brain tumor model is easy to develop and revealed variable reproducibility. This model can be applicable in radiologic imaging, treatment planning, interventional treatment and drug delivery research. VX2 cell can be successfully innoculated into the brain using variable methods under researcher's variable conditions.

15.
J Med Virol ; 95(2): e28558, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36755360

RESUMEN

The fourth vaccination dose confers additional protective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in individuals with no prior coronavirus disease-19 (COVID-19). However, its immunological benefit against currently circulating BA.4/5 is unclear in individuals who have received a booster shot and been infected with Omicron variant BA.1/2. We analyzed immune responses in whom had been boosted once and did not have COVID-19 (n = 16), boosted once and had COVID-19 when BA.1/2 was dominant in Korea (Hybrid-6M group, n = 27), and boosted twice and did not have COVID-19 (Vx4 group, n = 15). Antibody binding activities against RBDo BA.1 and RBDo BA.4/5 , antigen-specific memory CD4+ and CD8+ T-cell responses against BA.4/5, and B-cell responses against SARS-CoV-2 wild-type did not differ statistically between the Hybrid-6M and Vx4 groups. The humoral and cellular immune responses of the Hybrid-6M group against BA.4/5 were comparable to those of the Vx4 group. Individuals who had been boosted and had an Omicron infection in early 2022 may not have high priority for an additional vaccination.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Inmunidad Celular , Linfocitos B , Anticuerpos Neutralizantes , Anticuerpos Antivirales
16.
J Cereb Blood Flow Metab ; 43(6): 856-868, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36748316

RESUMEN

A substantial proportion of acute stroke patients fail to recover following successful endovascular therapy (EVT) and injury to the brain and vasculature secondary to reperfusion may be a contributor. Acute stroke patients were included with: i) large vessel occlusion of the anterior circulation, ii) successful recanalization, and iii) evaluable MRI early after EVT. Presence of hyperemia on MRI perfusion was assessed by consensus using a modified ASPECTS. Three different approaches were used to quantify relative cerebral blood flow (rCBF). Sixty-seven patients with median age of 66 [59-76], 57% female, met inclusion criteria. Hyperemia was present in 35/67 (52%) patients early post-EVT, in 32/65 (49%) patients at 24 hours, and in 19/48 (40%) patients at 5 days. There were no differences in incomplete reperfusion, HT, PH-2, HARM, severe HARM or symptomatic ICH rates between those with and without early post-EVT hyperemia. A strong association (R2 = 0.81, p < 0.001) was found between early post-EVT hyperemia (p = 0.027) and DWI volume at 24 hours after adjusting for DWI volume at 2 hours (p < 0.001) and incomplete reperfusion at 24 hours (p = 0.001). Early hyperemia is a potential marker for cerebrovascular injury and may help select patients for adjunctive therapy to prevent edema, reperfusion injury, and lesion growth.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Hiperemia , Daño por Reperfusión , Accidente Cerebrovascular , Humanos , Femenino , Masculino , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Isquemia Encefálica/tratamiento farmacológico , Trombectomía
17.
J Stroke Cerebrovasc Dis ; 32(1): 106870, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36434858

RESUMEN

OBJECTIVES: To evaluate the association between post-endovascular thrombectomy (EVT) blood-brain barrier (BBB) disruption on MRI or CT and average systolic blood pressure (SBP) with favorable 90-day functional outcome. Observational studies have found elevated SBP associated with worse outcomes post-EVT, while recent randomized trials found no difference in targeted BP reduction. There may be a subgroup of patients who benefit from targeted BP reduction post-EVT. METHODS: This is a single-center study of 1) anterior large vessel occlusion stroke patients treated with EVT from 2015 to 2021, 2) achieved mTICI grade 2b or 3. Hyperintense acute reperfusion marker (HARM), hemorrhagic transformation (HT), and midline shift at 3 h post-EVT and 24 h imaging were assessed independently by multiple raters. Binary logistic regression models were used to determine the association of post-EVT SBP with outcomes. BBB disruption was defined as HT or HARM on 3h post-EVT imaging. RESULTS: Of 103 patients, those with SBP 100-129 versus SBP 130-160 found no significant difference in favorable 90-day outcome (64% vs. 46%, OR 2.11, 95% CI 0.78-5.76, p=0.143). However, among 71 patients with BBB disruption, a significant difference in favorable outcome of 64% in SBP 100-129 vs. 39% in SBP 130-160 group (OR 5.93, 95% CI 1.50-23.45, p=0.011) was found. There was no difference in symptomatic ICH, 90-day mortality, midline shift (≥5 mm), and hemicraniectomy, between BP or BBB groups. CONCLUSIONS: BBB disruption on 3h post-EVT imaging and lower SBP was associated with favorable outcome. This imaging finding may guide targeted BP therapy and suggests need for a randomized control trial.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Hipotensión , Accidente Cerebrovascular , Humanos , Presión Sanguínea/fisiología , Barrera Hematoencefálica/diagnóstico por imagen , Resultado del Tratamiento , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Trombectomía/efectos adversos , Trombectomía/métodos , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos
18.
Korean J Radiol ; 23(7): 752-762, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35695313

RESUMEN

OBJECTIVE: To compare a deep learning-based reconstruction (DLR) algorithm for pediatric abdominopelvic computed tomography (CT) with filtered back projection (FBP) and iterative reconstruction (IR) algorithms. MATERIALS AND METHODS: Post-contrast abdominopelvic CT scans obtained from 120 pediatric patients (mean age ± standard deviation, 8.7 ± 5.2 years; 60 males) between May 2020 and October 2020 were evaluated in this retrospective study. Images were reconstructed using FBP, a hybrid IR algorithm (ASiR-V) with blending factors of 50% and 100% (AV50 and AV100, respectively), and a DLR algorithm (TrueFidelity) with three strength levels (low, medium, and high). Noise power spectrum (NPS) and edge rise distance (ERD) were used to evaluate noise characteristics and spatial resolution, respectively. Image noise, edge definition, overall image quality, lesion detectability and conspicuity, and artifacts were qualitatively scored by two pediatric radiologists, and the scores of the two reviewers were averaged. A repeated-measures analysis of variance followed by the Bonferroni post-hoc test was used to compare NPS and ERD among the six reconstruction methods. The Friedman rank sum test followed by the Nemenyi-Wilcoxon-Wilcox all-pairs test was used to compare the results of the qualitative visual analysis among the six reconstruction methods. RESULTS: The NPS noise magnitude of AV100 was significantly lower than that of the DLR, whereas the NPS peak of AV100 was significantly higher than that of the high- and medium-strength DLR (p < 0.001). The NPS average spatial frequencies were higher for DLR than for ASiR-V (p < 0.001). ERD was shorter with DLR than with ASiR-V and FBP (p < 0.001). Qualitative visual analysis revealed better overall image quality with high-strength DLR than with ASiR-V (p < 0.001). CONCLUSION: For pediatric abdominopelvic CT, the DLR algorithm may provide improved noise characteristics and better spatial resolution than the hybrid IR algorithm.


Asunto(s)
Aprendizaje Profundo , Interpretación de Imagen Radiográfica Asistida por Computador , Adolescente , Algoritmos , Niño , Preescolar , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
20.
J Clin Med ; 11(10)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35628886

RESUMEN

BACKGROUND: Magnetic resonance enterography (MRE) and capsule endoscopy (CE) are currently used for the evaluation of small bowel involvement in pediatric Crohn's disease (CD). Several studies have been conducted to investigate the usefulness and diagnostic accuracy of each test. However, only a few studies have been conducted to compare the performance of both tests in the assessment of pediatric small bowel CD upon diagnosis and during follow-up. Therefore, the purpose of this study was to assess the diagnostic accuracy and diagnostic consistency of CE and MRE for the evaluation of pediatric small bowel CD at the time of diagnosis and during follow-up. METHODS: Fifteen patients with pediatric CD were recruited for this study. They underwent MRE and CE concomitantly at the time of diagnosis and 10-12 weeks and one year after induction therapy for CD. MRE was interpreted using MRE global score (MEGS) and bowel wall inflammation severity diffusion-weighted imaging score (BWI-DWIS), whereas CE was interpreted using Lewis's score (LS). The two diagnostic modalities were then compared. RESULTS: Eleven patients completed MRE and CE at the time of diagnosis. Analysis of the results showed that LS had a strong correlation with MEGS and BIS-DWIS (ρ = 0.633, p = 0.037, and ρ = 0.629, p = 0.038, respectively). Nine patients completed three MREs and three CEs. LS significantly decreased throughout the sessions (p = 0.044), whereas MEGS and BIS-DWIS did not show any statistically significant changes. When LS was compared with MEGS and BIS-DWIS, both MRE indicators showed statistically significant differences throughout the sessions. CONCLUSIONS: At the time of diagnosis, the severity indexes of MRE and CE showed very good agreement. However, throughout management, MRE and CE did not show consistent changes.

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