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Deep learning-based prediction of split glomerular filtration rate with 99mTc-diethylenetriamine pentaacetic acid renal scan
No full textPurpose: To automate glomerular filtration rate (GFR) measurement by developing deep learning (DL) models for generating automated regions of interest (ROIs) on 99mTc-diethylenetriamine pentaacetic acid (99mTc-DTPA) renal scans and/or for directly regressing the GFR from the 99mTc-DTPA renal scans. Methods: Manually-drawn ROIs as well as the corresponding GFR values were retrieved from a Picture Archiving and Communications System were used as ground-truth (GT) (or silver standard) labels and target values, respectively. To this end, we developed two models: one using a two-dimensional U-Net convolutional neural network (CNN) architecture (ROI generator network) with multichannel input to automatically generate kidney and background ROIs, from which GFR was calculated using the Gates formula, and another model using a two-dimensional encoder CNN architecture (GFR regressor network) with multichannel input to directly predict GFR values without the need for ROIs, respectively. The agreement between GFR values from GT and DL ROIs was evaluated using Lin’s concordance correlation coefficient (CCC) and slope coefficients for linear regressor analyses. Bias and 95% limits of agreement (LOA) were assessed using Bland-Altman plots. Results: A total of 24364 scans (12821 patients) were included. Regarding the ROI generator network, we found excellent concordance between GT and DL GFR for left (CCC 0.982, 95% confidence interval [CI] 0.981–0.982; slope 1.004, 95% CI 1.003–1.004), for right (CCC 0.969, 95% CI 0.968–0.969; slope 0.954, 95% CI 0.953–0.955), and for both kidneys (CCC 0.978, 95% CI 0.978–0.979; slope 0.979, 95% CI 0.978–0.979). Bland-Altman analysis revealed minimal bias between GT and DL GFR, with mean differences of −0.2 (95% LOA −4.4–4.0), 1.4 (95% LOA −3.5–6.3) and 1.2 (95% LOA −6.5–8.8) mL/min/1.73 m² for left, right and both kidneys, respectively. Regarding the regressor network, GT and DL estimated GFR values is as follows for the left kidney (CCC 0.969, 95% CI 0.969–0.970), right kidney (CCC 0.969, 95% CI 0.968–0.969), and for both kidneys (CCC 0.972, 95% CI 0.971–0.972). Bland-Altman analysis revealed with mean differences of −0.06 (95% LOA −5.5–5.4), 0.15 (95% LOA −5.4–5.7) and 0.08 (95% LOA −8.9–9.1) mL/min/1.73 m² for left, right and both kidneys. Notably, 19960 scans (81.9%) showed an absolute difference in GFR of less than 5 mL/min/1.73 m² by the ROI generator network. Similarly, the regressor network showed an absolute difference in GFR of less than 5 mL/min/1.73 m² in 18,770 scans (77.0%). Conclusion: Our ROI generator network and GFR regressor network exhibited excellent performance in the generation of ROIs and estimate GFR on 99mTc-DTPA renal scans. This automated approach could potentially reduce manual effort and enhance the precision of GFR measurement in clinical practice.Maste
Clinical practice guidelines for esophagogastric junction cancer: Upper GI Oncology Summit 2023
No full textA Study on Metaformer based Motor Failure Diagnosis
No full textAs electric motors are widely used as the main power source, the demand for reliability and efficiency is increasing. As a result, the importance of early fault diagnosis of motor failures has been emphasized. To overcome the limitations of model-based fault diagnosis, we perform our work based on data-based fault diagnosis techniques. In this paper, we introduce LSTMFormer, which improves the performance of motor fault diagnosis by combining Metaformer structure and LSTM. To verify the proposed algorithm, we utilize the electrical fault data set of synchronous motors. The experimental results show excellent performance with an average accuracy of 99.79% and an average F1-score of 1. This indicates that the model can classify most faults and shows balanced performance in various fault types. In addition, it progresses learning stably and achieves high performance with a few of learning iterations. These results verify the effectiveness of the algorithm proposed in this paper
A Extension of the Animosity Model to the Global Brand
No full textKlein et al.(1998)은 반감모형을 제시하여 반감이 외국 제품의 구매의도에 미치는 영향을 추정하였으나 본 연구는 반감모형을 확장하여 반감이 외국 글로벌상표의 구매의도에 미치는 영향을 추정하였다. 반감의 대상국으로 일본을 선정하였다. 외국 브랜드로 일본의 유니클로 의류 브랜드를 선정하여 추가적으로 상표의 글로벌 지각이 미치는 영향을 추정하였다. 또한 품질평가와 소비자 민족중심주의(consumer ethnocentrism)를 통제변수로 추가하였다. 실증분석결과 전쟁반감과 경제적 반감 모두 구매의도에 유의하게 부정적으로 영향을 미치는 것으로 나타나고 있으며 글로벌 지각은 유의하게 긍정적으로 영향을 미치는 것으로 나타나고 있다. 또한 브랜드 평가는 유의하게 긍정적 영향을 미치는 것으로 나타나고 있으나 민족중심주의는 유의한 영향을 미치지 않는 것으로 나타나고 있다. 글로벌 지각은 브랜드 평가에도 유의하게 영향을 미쳐 글로벌 브랜드의 지각된 품질을 높이는 것으로 나타났다. 실증결과에 따른 논의 및 관리적 시사점과 연구의 한계 및 미래연구를 제시하였다.
This study tried to estimate the effects of animosity on the purchase intention of the global brand based on Klein et al.(1998)'s animosity model. Uniclo, a Japanese brand was chosen as the foreign brand and the effect of the perceived globalness was estimated. In addition, quality judgement and consumer ethnocentrism were added as control variables. The results showed that both war animosity and economic animosity were significant. Perceived globalness was also significant. Quality judgement was significant but consumer ethnocentrism was not significant. Finally discussions, managerial implication, limitations and suggestions for future study are provided
CD8+ cell dominance in immune checkpoint inhibitor-induced colitis and its heterogeneity across endoscopic features
No full textBackground: Immune checkpoint inhibitor (ICI)-induced colitis is a significant adverse event associated with ICI therapy, known to be linked to increased cytotoxic T-cell activity.
Objectives: To compare T-cell subsets based on the endoscopic features of ICI-induced colitis and to compare these findings with those of inflammatory bowel disease (IBD).
Design: Prospective cohort study.
Methods: We analyzed patients with ICI-induced colitis, confirmed through both endoscopic and histological evaluation. Biopsy specimens were examined using multiplex immunohistochemistry to assess their immune cell profile. Clinical outcomes were analyzed. Immune cell profiles were compared based on their endoscopic features and contrasted with those of patients with IBD.
Results: Seventeen patients with ICI-induced colitis were included in the study. All patients showed clinical improvement after treatment, and steroids were administered to 11 patients (64.7%). Based on endoscopic features, the patients were classified as Crohn's disease (CD)-like (n = 3, 17.6%), ulcerative colitis (UC)-like (n = 9, 52.9%), or microscopic colitis (MC)-like (n = 5, 29.4%). In ICI-induced colitis, cytotoxic T cells (Tc cells) were more predominant than helper T cells (Th cells) (p = 0.053), and this trend was most pronounced in the MC-like subtype (p = 0.020). When comparing the number of CD8+ cells infiltrating the crypts, both the UC-like and MC-like subtypes had significantly more infiltrating cells than the CD-like subtype (p = 0.008 and p = 0.016, respectively). In comparison to IBD, IBD exhibited a Th-dominant profile, whereas CD-like ICI-induced colitis had a lower Th cell density than CD (p = 0.032) and UC-like ICI-induced colitis had a higher Tc density than UC (p = 0.045).
Conclusion: Analysis of T-cell subsets of ICI-induced colitis revealed a Tc-dominant profile, contrasting with the Th dominance observed in patients with IBD. The Tc-dominant profile was evident in UC-like and MC-like subtypes, with significant crypt infiltration by CD8+ cells. Tc may play an important role in the pathophysiology of ICI-induced colitis
Reverse Transcription-PCR-based Sanger Sequencing-confirmed Exon-skipping Effect of a Novel GEN1 Intronic Variant (c.1408+4A>G)
No full textOptimal design of pma-synrm for e-bike traction motor using adaptive interpolation robustness optimization algorithm
No full textThis paper proposes an adaptive interpolation robustness optimization algorithm (AIROA) for the robust optimal design of a permanent magnet assisted synchronous reluctance motor for electric bicycle (EB) traction. The AIROA can drastically reduce the number of function calls to converge to an optimal solution by interpolating the problem regions. Especially, the AIROA effectively adjusts the number of generated samples using the diversification strategy with novel initial sampling strategy. Moreover, in the intensive searching strategy, the calculation time for generating a surrogate model and the accuracy of the solutions of the surrogate model can be enhanced as the AIROA adjusts the resolution of the interpolation near the roughly found solutions. At the end of the algorithm, a robustness test strategy is conducted, and a robust optimal solution is determined considering the accuracy of the interpolated uncertainty band of both global and local solutions. The superior performance of the AIROA was verified by two mathematical test functions. The applicability of the practical motor design was verified by applying the AIROA to the optimal design of the EB traction motor and successfully deriving the robust optimum design. The prototype motor was manufactured, and further validation was conducted by comparing the experimental results
Application of clinical decision support tools for predicting outcomes with vedolizumab therapy in patients with inflammatory bowel disease: A KASID multicentre study
No full textBackground/aim: We aimed to validate clinical decision support tools (CDSTs) to predict real-life effectiveness of vedolizumab (VDZ) in patients with inflammatory bowel disease.
Methods: We retrospectively enrolled patients with Crohn's disease (CD) or ulcerative colitis (UC) treated with VDZ at 10 tertiary referral centres in Korea between January 2017 and November 2021. We assessed clinical remission (CREM) and response (CRES), corticosteroid-free clinical remission (CSF-CREM) and response (CSF-CRES), biochemical response based on C-reactive protein (BioRES[CRP]) and faecal calprotectin (BioRES[FC]), endoscopic healing (EH), and the need to optimise or switch drugs based on CDST-defined response groups. Additionally, the area under the receiver operating characteristics curve (AUC) for the CDSTs was calculated.
Results: We included 143 patients with CD and 219 with UC. We observed incremental trends on CSF-CRES at week 14 (W14) (ptrend = 0.004) and decreasing trends for the need to optimise or switch drugs (ptrend = 0.016) in CD from the low to high probability groups. Except for CSF-CREM at W54, we noticed incremental trends for all clinical responses at W14, W26 and W54 (ptrend 0.600, whereas CDSTs showed poor accuracy in CD.
Conclusions: CDSTs for VDZ had acceptable accuracy in predicting effectiveness outcomes including clinical and biochemical outcomes in UC. However, their utility in CD was limited
Effects of Balanced Versus Saline-based Solutions on Acute Kidney Injury in Off-pump Coronary Artery Bypass Surgery: A Randomized Controlled Trial
No full textObjectives
To determine whether balanced solutions can reduce the incidence of acute kidney injury after off-pump coronary artery bypass surgery compared with saline.
Design
Randomized controlled trial.
Setting
Single tertiary care center.
Participants
Patients who underwent off-pump coronary artery bypass surgery between June 2014 and July 2020.
Interventions
Balanced solution-based chloride-restrictive intravenous fluid strategy.
Measurements and Main Results
The primary outcome was acute kidney injury within 7 postoperative days, as defined by the 2012 Kidney Disease: Improving Global Outcomes Clinical Practice Guideline. The incidence of acute kidney injury was 4.4% (8/180) in the balanced group and 7.3% (13/178) in the saline group. The difference was not statistically significant (risk difference, -2.86%; 95% confidence interval [CI], -7.72% to 2.01%; risk ratio, 0.61, 95% CI, 0.26 to 1.43; p = 0.35). Compared with the balanced group, the saline group had higher levels of intraoperative serum chloride and lower base excess, which resulted in a lower pH.
Conclusions
In patients undergoing off-pump bypass surgery with a normal estimated glomerular filtration rate, the intraoperative balanced solution-based chloride-restrictive intravenous fluid administration strategy did not decrease the rate of postoperative acute kidney injury compared with the saline-based chloride-liberal intravenous fluid administration strategy
Is it necessary to use a cervical brace after single- or double-level ACDF?
No full textAlthough anterior cervical discectomy and fusion (ACDF) is one of the most frequently performed spinal surgeries, there is no consensus regarding the necessity of prescribing a cervical brace after surgery. This study aimed to investigate any difference in radiological and clinical outcomes when wearing or not wearing cervical braces after single- or double-level ACDF. We examined 2 cohorts of patients who underwent single- or double-level ACDF surgery with and without a cervical brace: patients who underwent ACDF between March 2018 and December 2019 received a cervical brace, while patients who underwent ACDF between January 2020 and May 2021 did not. Each patient was evaluated radiologically and functionally using plain X-ray, modified Japanese Orthopedic Association score, and visual analog scale for neck and arm until 12 months after surgery. Fusion rate, subsidence, and postoperative complications were also evaluated. Eighty-three patients were included in the analysis: 38 were braced and 45 were not. The demographic characteristics and baseline outcome measures of both groups were similar. There was no statistically significant difference in any of the clinical measures at baseline. The modified Japanese Orthopedic Association score and visual analog scale for neck and arm were similar in both groups at all time intervals and showed statistically significant improvement when compared with preoperative scores. In addition, fusion rate, subsidence, and postoperative complications were similar in both groups. Our results suggest that the use of cervical braces does not improve the clinical outcomes of individuals undergoing single- or double-level ACDF