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1.
Biomaterials ; 265: 120408, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32992115

RESUMO

Degradable embolic agents that provide transient arterial occlusion during embolization procedures have been of interest for many years. Ideally, embolic agents are visible with standard imaging modalities and offer on-demand degradability, permitting physicians to achieve desired arterial occlusion tailored to patient and procedure indication. Subsequent arterial recanalization potentially enhances the overall safety and efficacy of embolization procedures. Here, we report on-demand degradable and MRI-visible microspheres for embolotherapy. Embolic microspheres composed of calcium alginate and USPIO nanoclusters were synthesized with an air spray atomization and coagulation reservoir equipped with a vacuum suction. An optimized distance between spray nozzle and reservoir allowed uniform size and narrow size distribution of microspheres. The fabricated alginate embolic microspheres crosslinked with Ca2+ demonstrated highly responsive on-demand degradation properties in vitro and in vivo. Finally, the feasibility of using the microspheres for clinical embolization and recanalization procedures was evaluated with interventional radiologists in rabbits. Digital subtraction angiography (DSA) guided embolization of hepatic arteries with these embolic microspheres was successfully performed and the occlusion of artery was confirmed with DSA images and contrast enhanced MRI. T2 MRI visibility of the microspheres allowed to monitor the distribution of intra-arterial (IA) infused embolic microspheres. Subsequent on-demand image-guided recanalization procedures were also successfully performed with rapid degradation of microspheres upon intra-arterial infusion of an ion chelating agent. These instant degradable embolic microspheres will permit effective on-demand embolization/recanalization procedures offering great promise to overcome limitations of currently available permanent and biodegradable embolic agents.

2.
Biomaterials ; 266: 120450, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33096376

RESUMO

Mesenchymal stem cells are the focus of intense research in bone development and regeneration. The potential of microparticles as modulating moieties of osteogenic response by utilizing their architectural features is demonstrated herein. Topographically textured microparticles of varying microscale features are produced by exploiting phase-separation of a readily soluble sacrificial component from polylactic acid. The influence of varying topographical features on primary human mesenchymal stem cell attachment, proliferation and markers of osteogenesis is investigated. In the absence of osteoinductive supplements, cells cultured on textured microparticles exhibit notably increased expression of osteogenic markers relative to conventional smooth microparticles. They also exhibit varying morphological, attachment and proliferation responses. Significantly altered gene expression and metabolic profiles are observed, with varying histological characteristics in vivo. This study highlights how tailoring topographical design offers cell-instructive 3D microenvironments which allow manipulation of stem cell fate by eliciting the desired downstream response without use of exogenous osteoinductive factors.

3.
Molecules ; 25(21)2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33147823

RESUMO

Amyloid beta (Aß) peptide, one of the most important pathogenic traits of Alzheimer's disease (AD), invokes a cascade of oxidative damage and eventually leads to neuronal death. In the present study, baicalein, wogonin, and oroxylin A, main active flavones in Scutellaria baicalensis, were evaluated for their neuroprotective effects against Aß25-35-stimulated damage. All tested compounds decreased Aß25-35-induced ROS generation and cell cycle arrest. In particular, baicalein exhibited the strongest antioxidant activity. In addition, these compounds suppressed apoptosis by attenuating mitochondrial dysfunction such as loss of membrane potential, Ca2+ accumulation and Bax/Bcl-2 ratio. Furthermore, all tested flavones inhibited the expression of iNOS and COX-2, which resulted in suppressing inflammatory cytokines including TNF-α, NO, and PGE2. Noticeably, all compounds exhibited the anti-inflammatory effects through downregulating NF-κB/MAPK pathway. Especially, oroxylin A was effective against both p65 and IκBα, while wogonin and baicalein were suppressed phospho-p65 and phospho-IκBα, respectively. Taken together, baicalein, wogonin, and oroxylin A can effectively relieve Aß25-35-stimulated neuronal apoptosis and inflammation in PC12 cells via downregulating NF-κB/MAPK signaling pathway.

4.
Nutrients ; 12(11)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182607

RESUMO

Excessive expression of interleukin (IL)-1ß in the brain causes depression and cognitive dysfunction. Herein, we investigated the effect of Lactobacillus gasseri NK109, which suppressed IL-1ß expression in activated macrophages, on Escherichia coli K1-induced cognitive impairment and depression in mice. Germ-free and specific pathogen-free mice with neuropsychiatric disorders were prepared by oral gavage of K1. NK109 alleviated K1-induced cognition-impaired and depressive behaviors, decreased the expression of IL-1ß and populations of NF-κB+/Iba1+ and IL-1R+ cells, and increased the K1-suppressed population of BDNF+/NeuN+ cells in the hippocampus. However, its effects were partially attenuated by celiac vagotomy. NK109 treatment mitigated K1-induced colitis and gut dysbiosis. Tyndallized NK109, even if lysed, alleviated cognitive impairment and depression. In conclusion, NK109 alleviated neuropsychiatric disorders and colitis by modulating IL-1ß expression, gut microbiota, and vagus nerve-mediated gut-brain signaling.

5.
Ann Transplant ; 25: e925229, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33154345

RESUMO

BACKGROUND Given that pregnancy is an immune-sensitizing event, female kidney transplant recipients who receive allografts from their offspring or husbands may have a higher risk of rejection and graft failure due to pre-sensitization acquired during pregnancy or childbirth. We investigated the association between donor relatedness (i.e., offspring, husband, unrelated) and graft survival among female living-donor kidney transplant (LDKT) recipients with pregnancy histories. MATERIAL AND METHODS From January 2009 to January 2018, a total of 2060 LDKTs were performed at Asan Medical Center, Seoul, Korea. After excluding HLA-incompatible transplantation, re-transplantation, and those without a clear history of childbirth, 390 female recipients were included and categorized into group I (offspring-to-mother, n=175), group II (husband-to-wife, n=159), and group III (unrelated, n=56). The primary endpoint was biopsy-proven acute rejection (BPAR) and graft survival. We also evaluated delayed graft function (DGF), death-censored graft failure, and mortality. RESULTS Group I had the lowest number of HLA mismatches (p<0.001), and group II had the highest number of ABO-incompatible transplantations (p=0.005). At 5 years after transplant, graft survival and death-censored graft survival did not significantly differ among the 3 groups (graft survival: 96.0% vs. 95.5% vs. 93.3%, p=0.685; death-censored graft survival: 98.3% vs. 97.5% vs. 100%, p=0.732). Five-year BPAR-free survival showed no significant differences among the 3 groups (88.6 vs. 88.7 vs. 88.6%, p=0.842). Group II had the highest rate of clinical rejection (p=0.103) and DGF (p=0.174), but the difference was not statistically significant. CONCLUSIONS Female LDKT recipients with possible pregnancy-related pre-sensitization who received grafts from offspring or husbands did not show significantly worse clinical outcomes than those who received grafts from unrelated donors.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33198275

RESUMO

Using nationwide data from the Health Insurance Review and Assessment service, we assessed the impact of rotavirus vaccines, introduced in South Korea, in 2007, on changes in the prevalence of factors (age, sex, and geographic location) associated with rotavirus gastroenteritis (RVGE) and rotavirus-associated benign convulsions with mild gastroenteritis (RaCwG). We analyzed health records of children younger than 3 years who visited clinical facilities and were diagnosed with RVGE or RaCwG between 2007 and 2019. The annual mid-year population (MYP) was obtained from the Korean Statistical Information Service. The annual prevalence of RVGE, RaCwG and associated factors were statistically analyzed. Overall, 219,686, and 4032, children were confirmed to have RVGE and RaCwG, respectively. Although the annual prevalence of RVGE decreased significantly, that of RaCwG did not. The annual ratio of RaCwG to RVGE was significantly high. Compared to the prevalence of RVGE, the prevalence of RaCwG was significantly lower in rural areas. The age of RaCwG patients was significantly lower than that of the MYP and that of RVGE patients. The decrease in the number of RaCwG patients after rotavirus vaccination was not as pronounced as the decrease in the number of RVGE patients.

7.
In Vivo ; 34(6): 3171-3180, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33144421

RESUMO

BACKGROUND/AIM: The prognostic relevance of programmed cell death ligand-1 (PD-L1) protein expression in gastric cancer (GC) remains controversial. The aims of the present study were to determine the correlations between tumor cell (TC) and immune cell (IC) PD-L1 protein levels with prognosis, and to determine the correlation between PD-L1 expression and different molecular GC subtypes. MATERIALS AND METHODS: TC and IC PD-L1 protein levels were measured in 286 GC patients. The patients were classified according to the Cancer Genome Atlas and Asian Cancer Research Group guidelines using immunohistochemistry and in situ hybridization. RESULTS: TC and IC PD-L1 protein levels were positively correlated with patient survival. TC PD-L1 expression was negatively correlated with tumor grade. TC and IC PD-L1 expression was associated with improved prognosis in Epstein-Barr virus negative (EBV-), microsatellite instability (MSI) rather than microsatellite stability (MSS) subgroup GC patients. CONCLUSION: PD-L1 protein expression in TCs and ICs can be used as a prognostic indicator for GC patients, particularly in the EBV-, MSI, and MSS subgroups.

8.
Knee ; 27(6): 1942-1952, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33221692

RESUMO

PURPOSE: To evaluate (1) the outcome of PCL reconstruction with tibial suspensory fixation using a fovea landmark technique based on the tunnel position and serial change of the tunnel configuration after trans-tibial PCL reconstruction, and (2) whether suspensory fixation has any harmful effect on the outcome. METHODS: A total of 48 knees that underwent PCL reconstruction were included. The tunnel position was analyzed using CT. To analyze the tunnel configuration, the tunnel diameter, area, and volume were measured. To evaluate the outcome, pre- and postoperative International Knee Documentation Committee (IKDC) and Lysholm scores were analyzed. To evaluate stability, a side-to-side difference was evaluated using Telos stress radiographs. RESULTS: The greatest configurational change occurred at the mid-portion of tibial tunnel. There was a correlation between stability and tibial tunnel mid-portion configurational change (p < 0.01). Important correlations were found between the tunnel position and serial tunnel configuration between high femoral tunnel and widest site of femoral tunnel and tibia aperture (p < 0.01 and 0.04, respectively). The diameter of widest site of tibia tunnel increased when the tibia tunnel center moved toward the posterior margin of the tibia (p = 0.02) and the percentage of femoral tunnel volume enlargement increased when the tibia tunnel center moved toward the medial edge of the PCL fovea (p = 0.02). CONCLUSIONS: A high femoral tunnel, medial tibial tunnel, and posterior tibial tunnel were related to the serial configurational change. A suspensory tibial fixation produced significant configurational change around the mid-portion of the tibial tunnel, and it induced a negative effect on stability. LEVEL OF EVIDENCE: Level IV.

9.
PLoS One ; 15(11): e0241588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33180838

RESUMO

PURPOSE: To investigate the efficacy of botulinum toxin injection without electromyographic guidance for the treatment of consecutive esotropia. METHODS: A retrospective study was performed on 49 subjects with consecutive esotropia who received botulinum toxin injection in the medial rectus muscles without the use of electromyographic guidance. Treatment was considered successful if the final ocular alignment was orthotropic or esodeviation was ≤10 prism diopters (PD) during distant fixation. RESULTS: The mean age was 15.2 ± 8.3 years. The mean esodeviation before injection was 21.8 ± 9.1 PD at distance and 21.3 ± 8.3 PD at near. The mean number of injections per patient was 1.3 ± 0.7, and 46 patients (93.9%) received two or fewer injections. At 6 months after the final injection, the mean angle of esodeviation was 7.3 ± 6.0 PD at distance and 7.5 ± 6.6 PD at near (all p<0.001), and 69.4% showed successful alignment. By multivariate analysis, an initial postoperative esodeviation of ≤18 PD at one month after exotropia surgery was considered to be a predictive factor for successful botulinum toxin injection (P = 0.007). Vertical deviation and/or ptosis occurred in 4 patients (8.2%) at two weeks after injection, which all resolved within three months. There was no recurrence of exotropia up to the final follow-up examination. CONCLUSION: Botulinum toxin injection without electromyographic guidance is safe and effective in the treatment of consecutive esotropia without causing recurrent exotropia. Successful botulinum toxin injection is likely in patients with an initial postoperative esodeviation of 18PD or less at one month after exotropia surgery.

10.
Bioorg Chem ; 105: 104397, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33130348

RESUMO

The study of a Hawaiian volcanic soil-associated fungal strain Penicillium herquei FT729 led to the isolation of one unprecedented benzoquinone-chromanone, herqueilenone A (1) and two phenalenone derivatives (2 and 3). Their structures were determined through extensive analysis of NMR spectroscopic data and gauge-including atomic orbital (GIAO) NMR chemical shifts and ECD calculations. Herqueilenone A (1) contains a chroman-4-one core flanked by a tetrahydrofuran and a benzoquinone with an acetophenone moiety. Plausible pathways for the biosynthesis of 1-3 are proposed. Compounds 2 and 3 inhibited IDO1 activity with IC50 values of 14.38 and 13.69 µM, respectively. Compounds 2 and 3 also demonstrated a protective effect against acetaldehyde-induced damage in PC-12 cells.

11.
Emerg Microbes Infect ; : 1-29, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33138739

RESUMO

As another wave of COVID-19 outbreak has approached in July 2020, a larger scale COVID-19 pediatric Asian cohort summarizing the clinical observations is warranted. Children confirmed with COVID-19 infection from the Republic of Korea, the Hong Kong Special Administrative Region (HKSAR) and Wuhan, China, during their first waves of local outbreaks were included. Their clinical characteristics and the temporal sequences of the first waves of local paediatric outbreaks were compared. 423 children with COVID-19 were analyzed. Wuhan had the earliest peak, followed by Korea and HKSAR. Compared with Korea and Wuhan, patients in HKSAR were significantly older (mean age: 12.9 vs. 10.8 vs. 6.6 years, p<0.001, respectively) and had more imported cases (87.5% vs. 16.5% vs. 0%, p<0.001, respectively). The imported cases were also older (13.4 vs. 7.6 years, p<0.001). More cases in HKSAR were asymptomatic compared to Korea and Wuhan (45.5% vs. 22.0% vs. 20.9%, p<0.001, respectively), and significantly more patients from Wuhan developed fever (40.6% vs. 29.7% vs. 21.6%, p=0.003, respectively). There were significantly less imported cases than domestic cases developing fever after adjusting for age and region of origin (p=0.046). 5.4% to 10.8% of patients reported anosmia and ageusia. None developed pediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (PMIS-TS). In general, adolescents were more likely to be asymptomatic and less likely to develop fever, but required longer hospital stays. In conclusion, majority patients in this pediatric Asian cohort had a mild disease. None developed PIMS-TS. Their clinical characteristics were influenced by travel history and age.

12.
J Vasc Interv Radiol ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33132027

RESUMO

PURPOSE: To determine the value of preprocedural MR imaging in genicular artery embolization (GAE) for patients with osteoarthritic knee pain. MATERIALS AND METHODS: This single-center study retrospectively analyzed 28 knees in 18 patients who underwent GAE for intractable knee pain < 1 month after MR imaging. The pain experienced in each knee was evaluated on a 100-mm visual analog scale (VAS) at baseline and 1- and 3-month after GAE. "GAE responders" were defined as knees that exhibited greater than 30% reduction of VAS pain scores from baseline at both follow-up visits. Musculoskeletal radiologists evaluated MR images of the affected knee compartment regarding cartilage defects, osteophytes, subchondral cysts, bone marrow lesions (BMLs), meniscal injury, and joint effusion. The performances of Kellgren-Lawrence (KL) grading and MR findings in predicting GAE responders was estimated based on receiver operating characteristic curves. RESULTS: The mean VAS pain score was 84.3 mm. BML (area under the curve [AUC], 0.860; P < .001), meniscal injury (AUC, 0.811; P = .003), and KL grading (AUC, 0.898; P < .001) were significantly associated with GAE outcome. To predict GAE responders, KL grade ≤ 2 yielded a sensitivity of 87.5% and a specificity of 60.9%, BML grade ≤ 1 yielded a sensitivity of 75.0% and a specificity of 69.6%, and meniscal injury grade ≤ 2 yielded a sensitivity of 83.3% and a specificity of 72.7%. CONCLUSIONS: Large BMLs and severe meniscal injuries on MR imaging, as well as high KL grades, indicated poor responses to GAE.

13.
Phytother Res ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33205558

RESUMO

In this study, we investigated whether total saponin extract (TSE), ginsenoside Rb1, and Rb1 metabolite compound K, which are isolated from red ginseng, have antinociceptive effects on peripheral and central neuropathic pain (PNP and CNP, respectively). PNP and CNP were induced by tail nerve injury (TNI) at S1 and by contusive spinal cord injury (SCI) at T9 in male Sprague-Dawley rats, respectively. Two weeks after TNI or 4 weeks after SCI, pain-induced rats were orally administered vehicle, TSE (50 mg/kg), Rb1 (12.5 mg/kg), compound K (7 mg/kg), or gabapentin (GBP, 60 mg/kg), and the antinociceptive effects were examined by von Frey filament, cold/warm water, and hot plate analyses. Allodynia and hyperalgesia were significantly alleviated by TSE, Rb1, and GBP 1 hr after drug administration. The immunohistochemistry and real-time RT-PCR results showed that the activation of microglia/astrocytes and the expression of inflammatory mediators such as Il-1ß, Il-6, iNOS, and Cox-2 were also significantly inhibited in L4-L5 spinal cord of CNP-induced rats 1 hr after drug administration. Furthermore, the antinociceptive effects of TSE and Rb1 were reversed by treatment with the estrogen receptor (ER) antagonist ICI182780. In particular, compound K also significantly alleviated both PNP and CNP. Therefore, our results indicate that TSE, Rb1, and compound K have potential antinociceptive effects against neuropathic pain that might be mediated through the ER.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33135478

RESUMO

We demonstrate the marked activity of SW033291, an inhibitor of 15-hydoxyprostaglandin dehydrogenase (15-PGDH), in preventing acute kidney injury (AKI) in a murine model of ischemia reperfusion injury. AKI due to ischemic injury represents a significant clinical problem. Prostaglandin E2 (PGE2) is vasodilatory in the kidney, but is rapidly degraded in vivo due to catabolism by 15-PGDH. We investigated the potential of SW033291, a potent and specific 15-PGDH inhibitor, as prophylactic treatment for ischemic AKI. Prophylactic administration of SW033291 significantly increased renal tissue PGE2 levels and increased post-AKI renal blood flow and renal arteriole area. In parallel, prophylactic SW033291 decreased post-AKI renal morphology injury score and tubular apoptosis and markedly reduced biomarkers of renal injury that included BUN, creatinine, NGAL and KIM-1. Prophylactic SW033291 also reduced post-AKI induction of proinflammatory cytokines, high mobility group box 1 (HMGB1), and malondialdehyde (MDA). Protective effects of SW033291 were mediated by PGE2 signaling as they could be blocked by pharmacologic inhibition of PGE2 synthesis. Consistent with activation of PGE2 signaling, SW033291 induced renal levels of both EP4 receptors and of cyclic adenosine monophosphate (cAMP), along with other vasodilatory effectors including AMP, adenosine, and the adenosine A2A receptor (A2A). Protective effects of SW0333291 could largely be achieved with a single prophylactic dose of drug. Inhibiting 15-PGDH may thus represent a novel strategy for prophylaxis of ischemic AKI in multiple clinical settings, including renal transplantation and cardiovascular surgery.

15.
Small ; : e2004372, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33136316

RESUMO

Next-generation energy storage devices such as lithium-sulfur batteries (LSBs) face several challenges including fast charging and high-power delivery. Thus, it is necessary to improve the stability of the electrodes with efficient electrochemical system. In this work, a durable sulfur cathode even at high rates is enabled via lean binder content. The binder consists of a chitosan cross-linked with a carboxylated nitrile-butadiene rubber (XNBR), which exhibits high affinity toward lithium polysulfide along with robust mechanical properties because of the synergistic effect of the polar chitosan and the elastomeric XNBR. Despite using extremely small content of binder (3 wt%), the LSB shows a highly stable long-term cycling performance with capacity retention decay values of 0.026% and 0.029% after 500 cycles at 5 and 10 C. Moreover, the cell shows an outstanding specific capacity of 228 mAh g-1 at an ultrahigh charge-discharge rate of 20 C. This approach may significantly improve the design of the sulfur cathode and pave a facile way to fabricate commercially viable next-generation energy storage devices.

16.
Otol Neurotol ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33177407

RESUMO

OBJECTIVE: To evaluate whether cochlear synaptopathy is a common pathophysiologic cause of tinnitus in individuals with normal audiograms. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. METHODS: We enrolled 27 subjects with unilateral tinnitus and normal symmetric hearing thresholds, and 27 age- and sex-matched control subjects with normal symmetric hearing thresholds. We measured 1) the amplitudes of waves I and V with 90 dB nHL click stimuli in quiet conditions; 2) the latency shift of wave V with 80 dB nHL click stimuli in background noise, varying from 40 dB HL to 70 dB HL; and 3) uncomfortable loudness levels (UCLs) at 500 Hz and 3000 Hz pure tones. RESULTS: There were no significant differences in the wave V/I amplitude ratio or the latency shift in wave V with increasing noise levels among the tinnitus ears (TEs), nontinnitus ears (NTEs), and control ears. There were no significant differences in UCLs at 500 Hz or 3000 Hz between TEs and NTEs, but the UCLs were lower in TEs (mean 111.3 dB or 104.1 dB) and NTEs (mean 109.4 dB or 100.6 dB) than in control ears (mean 117.9 dB or 114.1 dB, p < 0.017). No subject met our criteria for cochlear synaptopathy or increased central gain in terms of all three parameters. CONCLUSION: Based on these results for UCL, increased central gain is a major mechanism of tinnitus in humans with normal audiograms. However, this compensatory mechanism for reduced auditory input may originate from other pathophysiologic factors rather than from cochlear synaptopathy.

17.
Glycoconj J ; 37(6): 681-690, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33108606

RESUMO

In this study, we found that gene expression of the human ß-galactoside α2,6-sialyltransferase (hST6Gal I) was specifically increased during differentiation of human MG-63 osteoblastic cells by serum starvation (SS). In parallel, a distinct increase in binding to SNA, the α2,6-sialyl-specific lectin, was observed in serum-starved cells, as demonstrated by FACS analysis. 5'-Rapid amplification of cDNA ends analysis demonstrated that the increase of hST6Gal I transcript by SS is mediated by P1 promoter. To elucidate transcriptional regulation of hST6Gal I in SS-induced MG-63 cells, we functionally characterized the P1 promoter region of the hST6Gal I gene. The 5'-deletion analysis of P1 promoter region revealed that the 189 bp upstream region of transcription start site is critical for transcriptional activity of hST6Gal I gene in SS-induced MG-63 cells. This region contains the predicted binding sites for several transcription factors, including AREB6, FOXP1, SIX3, HNF1, YY2, and MOK2. The mutagenesis analysis for these sites and chromatin immunoprecipitation assay demonstrated that the YY2 binding site at -98 to -77 was essential for the SS-induced hST6Gal I gene expression during differentiation of MG-63 cells.

18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1055-1058, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018167

RESUMO

Cerebral Microbleeds (CMBs) are small chronic brain hemorrhages, which have been considered as diagnostic indicators for different cerebrovascular diseases including stroke, dysfunction, dementia, and cognitive impairment. In this paper, we propose a fully automated two-stage integrated deep learning approach for efficient CMBs detection, which combines a regional-based You Only Look Once (YOLO) stage for potential CMBs candidate detection and three-dimensional convolutional neural networks (3D-CNN) stage for false positives reduction. Both stages are conducted using the 3D contextual information of microbleeds from the MR susceptibility-weighted imaging (SWI) and phase images. However, we average the adjacent slices of SWI and complement the phase images independently and utilize them as a two- channel input for the regional-based YOLO method. The results in the first stage show that the proposed regional-based YOLO efficiently detected the CMBs with an overall sensitivity of 93.62% and an average number of false positives per subject (FPavg) of 52.18 throughout the five-folds cross-validation. The 3D-CNN based second stage further improved the detection performance by reducing the FPavg to 1.42. The outcomes of this work might provide useful guidelines towards applying deep learning algorithms for automatic CMBs detection.


Assuntos
Imagem por Ressonância Magnética , Redes Neurais de Computação , Algoritmos , Encéfalo , Hemorragia Cerebral/diagnóstico , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-33095332

RESUMO

PURPOSE: Osteoarthritis (OA) in the glenohumeral joint is a concomitant lesion with rotator cuff tear that commonly occurs in older patients. The authors aimed to evaluate the effect of associated OA on the treatment outcome of rotator cuff repair. METHODS: A total of three hundred and forty-eight patients who underwent full-thickness arthroscopic rotator cuff repair were retrospectively reviewed, and the data were prospectively collected. The severity of OA was evaluated using the Samilson and Prieto method preoperatively and the Outerbridge classification intraoperatively. The patients were divided into the small-to-medium group and large-to-massive group according to rotator cuff tear size and were evaluated for presence or absence of OA. The postoperative clinical outcomes were assessed using the visual analog scale for pain, simple shoulder test (SST), University of California-Los Angeles, Constant, and American Shoulder and Elbow Surgeons (ASES) scoring systems at baseline and at final follow-up. RESULTS: Forty-five patients were diagnosed with glenohumeral OA (12.9%). Overall, no significant differences were observed in demographic and baseline data between the two groups according to the presence or absence of OA. The clinical symptoms of both groups significantly improved at the final follow-up. At the final follow-up, no significant differences were found in the VAS for pain, SST, UCLA, Constant, and ASES scores between the two groups. In the large-to-massive tear group, patients with OA had significantly inferior clinical results compared with those without OA. CONCLUSION: The clinical outcome scores improved after rotator cuff repair regardless of the presence of concomitant OA. However, glenohumeral OA should be considered as a potential negative prognostic factor in patients with large-to-massive rotator cuff tears. LEVEL OF EVIDENCE: III.

20.
Sensors (Basel) ; 20(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066256

RESUMO

The single-hop star-of-stars topology in low-power and wide-area networks (LPWAN) exhibits reliability and substandard coverage issues, especially in urban areas where line-of-sight (LoS) communication is difficult to achieve. Moreover, LPWAN trade-off the data rate to achieve longer coverage, preventing other end-devices from using the time resource. Locating other gateways is uneconomical as it requires infrastructure, such as the internet and a power connection. In this study, we propose a forwarding scheme with a relay to increase LPWAN coverage and reliability while not degrading the network's capacity. A relay tends to incur unnecessary forwarding that degrades the network capacity unless proper countermeasure is prepared. Our works, namely opportunistic and on-demand network coding (OODC), minimize unnecessary forwarding and make good use of multiple-receiving relays. Network coding is also applied in the relay for better transmission efficiency and reliability simultaneously. Because network coding occurs header overhead, we perform a header compression technique to counter it. According to our simulation result, our method shows better reliability than fixed path forwarding. In an adaptive data rate settings, the OODC achieves a 92% packet delivery ratio (PDR), whereas a fixed-path forwarding only achieves an 84% PDR.

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