Kang, Jun-Koo;Chung, Jae-Wook;Chun, So Young;Ha, Yun-Sok;Choi, Seock Hwan;Lee, Jun Nyung;Kim, Bum Soo;Yoon, Ghil Suk;Kim, Hyun Tae;Kim, Tae-Hwan;Kwon, Tae Gyun
Journal of Yeungnam Medical Science
/
v.35
no.2
/
pp.171-178
/
2018
Background: To evaluate mid-term oncological and functional outcomes in patients with prostate cancer treated by robot-assisted laparoscopic radical prostatectomy (RALP) at our institution. Methods: We retrospectively reviewed the medical records of 128 patients with prostate cancer who underwent RALP at our institution between February 2008 and April 2010. All patients enrolled in this study were followed up for at least 5 years. We analyzed biochemical recurrence (BCR)-free survival using a Kaplan-Meier survival curve analysis and predictive factors for BCR using multivariate Cox regression analysis. Continence recovery rate, defined as no use of urinary pads, was also evaluated. Results: Based on the D'Amico risk classification, there were 30 low-risk patients (23.4%), 47 intermediaterisk patients (38.8%), and 51 high-risk patients (39.8%), preoperatively. Based on pathological findings, 50.0% of patients (64/128) showed non-organ confined disease (${\geq}T3a$) and 26.6% (34/128) had high grade disease (Gleason score ${\geq}8$). During a median follow-up period of 71 months (range, 66-78 months), the frequency of BCR was 33.6% (43/128) and the median BCR-free survival was 65.9 (0.4-88.0) months. Multivariate Cox regression analysis revealed that high grade disease (Gleason score ${\geq}8$) was an independent predictor for BCR (hazard ratio=4.180, 95% confidence interval=1.02-17.12, p=0.047). In addition, a majority of patients remained continent following the RALP procedure, without the need for additional intervention for post-prostatectomy incontinence. Conclusion: Our study demonstrated acceptable outcomes following an initial RALP procedure, despite 50% of the patients investigated demonstrating high-risk features associated with non-organ confined disease.
According to International Associating for the Study of Pain (IASP) definition, neuropathic pain is a disorder characterized by dysfunction of the nervous system that, under normal conditions, mediates virulent information to the central nervous system (CNS). This pain can be divided into a disease with provable lesions in the peripheral or central nervous system and states with an incorporeal lesion of any nerves. Both conditions undergo long-term and chronic processes of change, which can eventually develop into chronic pain syndrome, that is, nervous system is inappropriately adapted and difficult to heal. However, the treatment of neuropathic pain itself is incurable from diagnosis to treatment process, and there is still a lack of notable solutions. Recently, several studies have observed the responses of CNS to harmful stimuli using image analysis technologies, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), and optical imaging. These techniques have confirmed that the change in synaptic-plasticity was generated in brain regions which perceive and handle pain information. Furthermore, these techniques helped in understanding the interaction of learning mechanisms and chronic pain, including neuropathic pain. The study aims to describe recent findings that revealed the mechanisms of pathological pain and the structural and functional changes in the brain. Reflecting on the definition of chronic pain and inspecting the latest reports will help develop approaches to alleviate pain.
Objectives: To investigate efficacy of Korean medicine for patients with Parkinson's Disease (PD) with pain. Methods: We performed a retrospective review of the medical records for patients diagnosed with PD between 2012 and 2019 at Gangdong Kyung Hee University Korean Medicine Hospital in South Korea. Results: Twenty-two patients with King's Parkinson's Disease Pain Scale(KPPS) scores at least twice were analyzed for evaluating the efficacy of Korean medicine for pain treatment in PD. The mean total scores before and after Korean medicine treatment were 15.23±1 .01 and 9.2±8.7, respectively, and the mean difference between the before/after total scores was 6.0±5.8 (P<0.001). Specifically, the score of radicular pain was significantly decreased (P=0.048). Conclusions: These findings suggest that Korean medicine could be beneficial for reducing pain associated with PD. Clinical efficacy should be confirmed by further studies, such as large-sample cohort studies and randomized controlled trials to clarify the pathological pain relief mechanism and the analgesic effect of Korean medicine.
Purpose: To evaluate the CT features of incidental breast lesions on chest CT and to suggest useful criteria for referral to a specialized breast unit. Materials and Methods: Between May 2009 and April 2014, enhanced chest CT examination reports containing the key word 'breast' were reviewed retrospectively. Patients who had incidental breast lesion and were referred to a specialized breast unit and then underwent pathological confirmation or follow-up over a 1-year period were included. Finally, 86 patients (all female, mean age, $48.9{\pm}12.6years$) were enrolled. Two radiologists evaluated lesion characteristics, including size, shape, margins, and enhancement. The correlations between the CT features and pathologies were evaluated, and the diagnostic accuracy of CT features in various combinations was assessed. Results: Among the CT features, irregular shape, non-circumscribed margin, and high contrast enhancement were different between malignant and benign lesions (p < 0.05). The combination of non-circumscribed margin and high contrast enhancement had the highest accuracy (97.7%). Conclusion: Reliable CT features for incidental malignant breast masses are irregular shape, non-circumscribed margin, and high contrast enhancement. The combination of non-circumscribed margin and high contrast enhancement could help distinguish incidental malignant breast lesions and indicate referral to a specialized breast unit.
Purpose: Total or proximal gastrectomy of the upper-third early gastric cancer (u-EGC) often causes severe post-gastrectomy syndrome, suggesting that these procedures are extremely invasive for patients without pathologically positive lymph node (LN) metastasis. This study aimed to evaluate the clinical applicability of a stomach function-preserving surgery, local resection (LR), with prophylactic left gastric artery (LGA)-basin dissection (LGA-BD). Materials and Methods: The data of patients with u-EGC (pathologically diagnosed as T1) were retrospectively analyzed. Total gastrectomy was performed in 30 patients, proximal gastrectomy in 45, and subtotal gastrectomy in 6; the LN status was evaluated assuming that the patients had already underwent LR + LGA-BD. This procedure was considered feasible in patients without LN metastases or in patients with cancer in the LGA basin. The reproducibility of the results was also evaluated using an external validation dataset. Results: Of the 82 eligible patients, 79 (96.3%) were cured after undergoing LR + LGA-BD, 74 (90.2%) were pathologically negative for LN metastases, and 5 (6.1%) had LN metastases, but these findings were only observed in the LGA basin. Similarly, of the 406 eligible tumors in the validation dataset, 396 (97.5%) were potentially curative. Tumors in the lesser curvature, post-endoscopic resection status, and small tumors (<20 mm) were considered to be stronger indicators of LR + LGA-BD as all subpopulation cases met our feasibility criteria. Conclusions: More than 95% of the patients with u-EGC might be eligible for LR + LGA-BD. This function-preserving procedure may contribute to the development of u-EGC without pathological LN metastases, especially for tumors located at the lesser curvature.
Objectives : Neuroinflammation is a common pathological mechanism of neurodegenerative diseases, and the development of therapeutic agents is urgently needed. Red ginseng has been known to be good for the immune stimulation in Eastern Asia. Although the immuno-stimulatory activity of red ginseng are already known, the neuro-protective effects of cultivated red ginseng with fermented complex mushroom-cereal mycelium (RGFM) have not been conducted. Thus, in this study, we tried to investigate the anti-neuroinflammatory effect of RGFM water extract on lipopolysaccharide (LPS) stimulated BV2 cells. Methods : BV2 cells were pretreated with RGFM 1 h prior to LPS exposure. To determine the neuro-protective effects of RGFM water extract, we measured the expression of inflammatory mediators including inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and nitric oxide (NO) and pro-inflammatory cytokines such as interleukin (IL)-1𝛽, IL-6 and tumor necrosis factor (TNF)-𝛼 in LPS-stimulated BV2 cells. In addition, to find out the regulatory mechanism of RGFM water extract, we assessed the protein levels of mitogen-activated protein kinases (MAPKs) and inhibitory 𝜅B𝛼 (I𝜅B𝛼) by western blotting. Results : In our study, treatment of RGFM reduced the mRNA expression of iNOS and COX-2 and suppressed NO production in LPS-stimulated BV2 cells. Additionally, the secretion of IL-1𝛽 and TNF-𝛼 but not IL-6 was significantly inhibited by RGFM. Furthermore, RGFM water extract inhibited the phosphorylation of c-Jun N-terminal kinase (JNK). Conclusions : Taken together, these findings suggest that RGFM water extract has a protective effect on neuroinflammation through inhibition of JNK.
Kim, Da Hye;Hwangbo, Hyun;Lee, Hyesook;Cheong, Jaehun;Choi, Yung Hyun
Journal of Life Science
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v.32
no.9
/
pp.712-720
/
2022
The purpose of this study was to investigate the efficacy of rat corneal-derived epithelial cells as an in vitro model to evaluate the harmfulness of the cornea caused by particulate matter 2.5 (PM2.5). To establish an experimental model for the effect of PM2.5 on corneal epithelial cells, it was confirmed that primary cultured cells isolated from rat eyes were corneal epithelial cells through pan-cytokeratin staining. Our results showed that PM2.5 treatment reduced cell viability of primary rat corneal epithelial (RCE) cells, which was associated with the induction of apoptosis. PM2.5 treatment also increased the generation of reactive oxygen species due to mitochondrial dysfunction. In addition, the production of nitric oxide and inflammatory cytokines was increased in PM2.5-treated RCE cells. Furthermore, through heatmap analysis showing various expression profiling between PM2.5-exposed and unexposed RCE cells, we proposed five genes, including BLNK, IL-1RA, Itga2b, ABCb1a and Ptgs2, as potential targets for clinical treatment of PM-related ocular diseases. These findings indicate that the primary RCE cell line is a useful in vitro model system for the study of PM2.5-mediated pathological mechanisms and that PM2.5-induced oxidative and inflammatory responses are key factors in PM2.5-induced ocular surface disorders.
Dal-Ah Kim;Mi-Ran Lee;Hyung Jung Oh;Myong Kim;Kyoung Hye Kong
BMB Reports
/
v.56
no.3
/
pp.196-201
/
2023
Renal fibrosis is the final manifestation of chronic kidney disease (CKD) regardless of etiology. Hypoxia-inducible factor-2 alpha (HIF-2α) is an important regulator of chronic hypoxia, and the late-stage renal tubular HIF-2α activation exerts protective effects against renal fibrosis. However, its specific role in progressive renal fibrosis remains unclear. Here, we investigated the effects of the long-term tubular activation of HIF-2α on renal function and fibrosis, using in vivo and in vitro models of renal fibrosis. Progressive renal fibrosis was induced in renal tubular epithelial cells (TECs) of tetracycline-controlled HIF-2α transgenic (Tg) mice and wild-type (WT) controls through a 6-week adenine diet. Tg mice were maintained on doxycycline (DOX) for the diet period to induce Tg HIF-2α expression. Primary TECs isolated from Tg mice were treated with DOX (5 ㎍/ml), transforming growth factor-β1 (TGF-β1) (10 ng/ml), and a combination of both for 24, 48, and 72 hr. Blood was collected to analyze creatinine (Cr) and blood urea nitrogen (BUN) levels. Pathological changes in the kidney tissues were observed using hematoxylin and eosin, Masson's trichrome, and Sirius Red staining. Meanwhile, the expression of fibronectin, E-cadherin and α-smooth muscle actin (α-SMA) and the phosphorylation of p38 mitogen-activated protein kinase (MAPK) was observed using western blotting. Our data showed that serum Cr and BUN levels were significantly lower in Tg mice than in WT mice following the adenine diet. Moreover, the protein levels of fibronectin and E-cadherin and the phosphorylation of p38 MAPK were markedly reduced in the kidneys of adenine-fed Tg mice. These results were accompanied by attenuated fibrosis in Tg mice following adenine administration. Consistent with these findings, HIF-2α overexpression significantly decreased the expression of fibronectin in TECs, whereas an increase in α-SMA protein levels was observed after TGF-β1 stimulation for 72 hr. Taken together, these results indicate that long-term HIF-2α activation in CKD may inhibit the progression of renal fibrosis and improve renal function, suggesting that long-term renal HIF-2α activation may be used as a novel therapeutic strategy for the treatment of CKD.
Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN). AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.
Objective: To investigate the image quality of ultralow-dose CT (ULDCT) of the chest reconstructed using a cycle-consistent generative adversarial network (CycleGAN)-based deep learning method in the evaluation of pulmonary tuberculosis. Materials and Methods: Between June 2019 and November 2019, 103 patients (mean age, 40.8 ± 13.6 years; 61 men and 42 women) with pulmonary tuberculosis were prospectively enrolled to undergo standard-dose CT (120 kVp with automated exposure control), followed immediately by ULDCT (80 kVp and 10 mAs). The images of the two successive scans were used to train the CycleGAN framework for image-to-image translation. The denoising efficacy of the CycleGAN algorithm was compared with that of hybrid and model-based iterative reconstruction. Repeated-measures analysis of variance and Wilcoxon signed-rank test were performed to compare the objective measurements and the subjective image quality scores, respectively. Results: With the optimized CycleGAN denoising model, using the ULDCT images as input, the peak signal-to-noise ratio and structural similarity index improved by 2.0 dB and 0.21, respectively. The CycleGAN-generated denoised ULDCT images typically provided satisfactory image quality for optimal visibility of anatomic structures and pathological findings, with a lower level of image noise (mean ± standard deviation [SD], 19.5 ± 3.0 Hounsfield unit [HU]) than that of the hybrid (66.3 ± 10.5 HU, p < 0.001) and a similar noise level to model-based iterative reconstruction (19.6 ± 2.6 HU, p > 0.908). The CycleGAN-generated images showed the highest contrast-to-noise ratios for the pulmonary lesions, followed by the model-based and hybrid iterative reconstruction. The mean effective radiation dose of ULDCT was 0.12 mSv with a mean 93.9% reduction compared to standard-dose CT. Conclusion: The optimized CycleGAN technique may allow the synthesis of diagnostically acceptable images from ULDCT of the chest for the evaluation of pulmonary tuberculosis.
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