Machine Learning Approach Using Routine Immediate Postoperative Laboratory Values for Predicting Postoperative Mortality

Background: Several prediction models have been proposed for preoperative risk stratification for mortality. However, few studies have investigated postoperative risk factors, which have a significant influence on survival after surgery. This study aimed to develop prediction models using routine immediate postoperative laboratory values for predicting postoperative mortality. Methods: Two tertiary hospital databases were used in this research: one for model development and another for external validation of the resulting models. The following algorithms were utilized for model development: LASSO logistic regression, random forest, deep neural network, and XGBoost. We built the models on the lab values from immediate postoperative blood tests and compared them with the SASA scoring system to demonstrate their efficacy. Results: There were 3817 patients who had immediate postoperative blood test values. All models trained on immediate postoperative lab values outperformed the SASA model. Furthermore, the developed random forest model had the best AUROC of 0.82 and AUPRC of 0.13, and the phosphorus level contributed the most to the random forest model. Conclusions: Machine learning models trained on routine immediate postoperative laboratory values outperformed previously published approaches in predicting 30-day postoperative mortality, indicating that they may be beneficial in identifying patients at increased risk of postoperative death.

Asymptomatic Cerebral Vasoconstriction after Carotid Artery Stenting

BACKGROUND AND PURPOSE

Carotid artery stent placement is widely performed for treatment of carotid stenosis. The purpose of this study is to present our observations on cerebral vasoconstriction in ipsilateral anterior circulation during immediate poststenting angiography in patients with near-total occlusion of the proximal ICA.

MATERIALS AND METHODS

We retrospectively reviewed patient data from December 2008 to December 2018. There were 28 patients with carotid near-total occlusion. Two neuroradiologists reviewed the final cerebral angiographic finding of carotid artery stent placement to evaluate the presence of vasoconstriction or vasodilation.

RESULTS

A total of 28 patients with near-total occlusion (mean ± standard deviation age, 69.0 ± 6.5 years; 92.9% male) were analyzed. Ten patients showed vasoconstriction in the treated territory, and 18 patients did not show vasoconstriction after carotid artery stenting. There were no statistically significant differences in comorbidity, frequency of symptomatic lesions, antiplatelet medication, mean procedure time, and initial NIHSS and baseline modified Rankin scale scores between the 2 groups. However, vasoconstriction is more likely to happen in patients with isolated territory from the contralateral anterior and posterior circulation (66.7% in the isolated territory group and 12.5% in the not-isolated territory group; P < .05). No headache or neurologic deficit was noted in all 10 patients with cerebral vasoconstriction.

CONCLUSIONS

Cerebral vasoconstriction may occur after carotid artery stenting more frequently than expected. It occurs more frequently in patients with near-total occlusion and with isolation of the cerebral circulation. A large-scale study is necessary to assess the clinical implications of cerebral vasoconstriction after carotid artery stenting.

Clinical study on concurrent use of electro-acupuncture or Chuna manual therapy with pregabalin for chemotherapy-induced peripheral neuropathy: safety and effectiveness (open-labeled, parallel, randomized controlled trial, assessor-blinded): A study protocol

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the major side effects of chemotherapy. Its main symptoms are pain, paresthesia, and numbness. However, the mechanisms underlying the development of CIPN remain unclear and standard treatments have not been established. Recently, there has been a growing interest in various approaches to overcome the limitations of the existing treatments. This study aims to evaluate the efficacy and safety of the concurrent use of two complementary and alternative therapies: electroacupuncture (EA) and Chuna manual therapy (CMT), with pregabalin, which is the conventional pharmacotherapy for neuropathic pain.

METHODS/DESIGN

This is an open-label, parallel, assessor-blinded randomized controlled trial, which includes 90 patients with colorectal and breast cancer, who developed CIPN. After a 2-week preparation period, the patients are divided into three groups (pregabalin administration group, pregabalin + EA treatment group, and pregabalin + CMT treatment group), treated for approximately 5 weeks and followed-up 4 weeks after treatment. The primary outcome is assessed using the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group Neurotoxicity subscale score (version 4.0) and the secondary outcome is measured using the Quality of Life Questionnaire-CIPN 20-Item Scale (version 3.0) and the quality of life questionnaire (version 3.0) developed by the European Organisation for Research and Treatment of Cancer. Moreover, exploratory efficacy and safety evaluations will be conducted based on the chemotherapy-completion rate and nerve conduction studies.

MicroRNAs associated with microvascular invasion in hepatocellular carcinoma and their prognostic impacts in patients undergoing hepatic resection

Although microvascular invasion (McVI) has prognostic value for patients with hepatocellular carcinoma (HCC) who have undergone hepatic resection, few studies have investigated the relationship between McVI and the aberrant expression of microRNAs (miRNAs). The present study identified the miRNAs that were selectively expressed in HCC with McVI and investigated their prognostic value. Clinical data and the miRNA expression profiles of 372 patients with HCC were extracted from The Cancer Genome Atlas database. miRNAs that were differentially expressed between patients with McVI and those without vascular invasion (VI) were identified and investigated as potential prognostic factors for HCC. The results demonstrated that McVI was a significant predictor of shortened recurrence-free survival (RFS). The 3 year RFS rate in patients with HCC accompanied by McVI was 28.2 and 49.3% in HCC without VI (P<0.001). miRNA-141/-582/-9 were upregulated, while miRNA-675 was downregulated in patients with McVI when compared with HCC patients without VI. Log₂ fold-changes of miRNA-141/-582/-675/-9 were 0.80 [false discovery rate (FDR), 0.005], 0.55 (FDR, 0.045), -0.99 (FDR, 0.005) and 1.22 (FDR, <0.001), respectively. Kaplan-Meier analysis indicated that the overexpression of miR-141/-582/-9 was significantly associated with poor RFS and a poor overall survival. A text mining analysis revealed that these miRNAs were significantly associated with multifaceted hallmarks of cancer, including 'invasion and metastasis'. In conclusion, the overexpression of miRNA-141/-582/-9 was associated with McVI and a poor survival in patients undergoing hepatic resection for HCC.

Theragnosis by a miR-141-3p molecular beacon: simultaneous detection and sensitization of 5-fluorouracil resistant colorectal cancer cells through the activation of the TRIM13-associated apoptotic pathway

We developed a molecular beacon targeting miR-141-3p, aberrantly increased in 5-fluorouracil-resistant colorectal cancer cells (R-CRCCs). It consists of a fluorophore-labeled oligonucleotide, antisense to miR-141-3p, and a quencher. It detected R-CRCCs and recovered the chemosensitivity of them to 5-fluorouracil by hybridization with miR-141-3p, which is applicable to cancer treatment.

Exosome-Mediated Ultra-Effective Direct Conversion of Human Fibroblasts into Neural Progenitor-like Cells

Exosomes, naturally secreted nanoparticles, have been introduced as vehicles for horizontal transfer of genetic material. We induced autologous exosomes containing a cocktail of reprogramming factors ("reprosomes") to convert fibroblasts into neural progenitor cells (NPCs). The fibroblasts were treated with ultrasound and subsequently cultured in neural stem cell medium for 1 day to induce the release of reprosomes composed of reprogramming factors associated with chromatin remodeling and neural lineage-specific factors. After being treated with reprosomes, fibroblasts were converted into NPCs (rNPCs) with great efficiency via activation of chromatin remodeling, so quickly that only 5 days were required for the formation of 1500 spheroids showing an NPC-like phenotype. The rNPCs maintained self-renewal and proliferative properties for several weeks and successfully differentiated into neurons, astrocytes, and oligodendrocytes in vitro and in vivo. Reprosome-mediated cellular reprogramming is simple, safe, and efficient to produce autologous stem cells for clinical application.

Bioimaging of multiple piRNAs in a single breast cancer cell using molecular beacons

Simultaneous bioimaging of piR-36026 and piR-36743 using molecular beacons successfully visualized 4 different subtypes of breast cancer.

Multiplex bioimaging of piRNA molecular pathway-regulated theragnostic effects in a single breast cancer cell using a piRNA molecular beacon

Recently, PIWI-interacting small non-coding RNAs (piRNAs) have emerged as novel cancer biomarkers candidate because of their high expression level in various cancer types and role in the control of tumor suppressor genes. In this study, a novel breast cancer theragnostics probe based on a single system targeting the piRNA-36026 (piR-36026) molecular pathway was developed using a piR-36026 molecular beacon (MB). The piR-36026 MB successfully visualized endogenous piR-36026 biogenesis, which is highly expressed in MCF7 cells (a human breast cancer cell line), and simultaneously inhibited piR-36026-mediated cancer progression in vitro and in vivo. We discovered two tumor suppressor proteins, SERPINA1 and LRAT, that were directly regulated as endogenous piR-36026 target genes in MCF7 cells. Furthermore, multiplex bioimaging of a single MCF7 cell following treatment with piR-36026 MB clearly visualized the direct molecular interaction of piRNA-36026 with SERPINA1 or LRAT and subsequent molecular therapeutic responses including caspase-3 and PI in the nucleus.

Laparoscopic repair of parastomal and incisional hernias with a modified Sugarbaker technique

A parastomal hernia is the most common surgical complication following stoma formation. As the field of laparoscopic surgery advances, different laparoscopic approaches to repair of parastomal hernias have been developed. Recently, the Sugarbaker technique has been reported to have lower recurrence rates compared to keyhole techniques. As far as we know, the Sugarbaker technique has not yet been performed in Korea. We herein present a case report of perhaps the first laparoscopic parastomal hernia repair with a modified Sugarbaker technique to be successfully carried out in Korea. A 79-year-old woman, who underwent an abdominoperineal resection for an adenocarcinoma of the rectum 9 years ago, presented with a large parastomal and incisional hernias, and was treated with a laparoscopic repair with a modified Sugarbaker technique. Six months after surgery, follow-up with the patient has shown no evidence of recurrence.

Impact of diabetes on oncologic outcome of colorectal cancer patients: colon vs. rectal cancer

Background

To evaluate the impact of diabetes on outcomes in colorectal cancer patients and to examine whether this association varies by the location of tumor (colon vs. rectum).

Patients and methods

This study includes 4,131 stage I-III colorectal cancer patients, treated between 1995 and 2007 (12.5% diabetic, 53% colon, 47% rectal) in South Korea. Cox proportional hazards modeling was used to determine the prognostic influence of DM on survival endpoints.

Results

Colorectal cancer patients with DM had significantly worse disease-free survival (DFS) [hazard ratio (HR) 1.17, 95% confidence interval (CI): 1.00–1.37] compared with patients without DM. When considering colon and rectal cancer independently, DM was significantly associated with worse overall survival (OS) (HR: 1.46, 95% CI: 1.11–1.92), DFS (HR: 1.45, 95% CI: 1.15–1.84) and recurrence-free survival (RFS) (HR: 1.32, 95% CI: 0.98–1.76) in colon cancer patients. No association for OS, DFS or RFS was observed in rectal cancer patients. There was significant interaction of location of tumor (colon vs. rectal cancer) with DM on OS (P = 0.009) and DFS (P = 0.007).

Conclusions

This study suggests that DM negatively impacts survival outcomes of patients with colon cancer but not rectal cancer.

Safety and efficacy of the NiTi Shape Memory Compression Anastomosis Ring (CAR/ColonRing) for end-to-end compression anastomosis in anterior resection or low anterior resection

PURPOSE

Compression anastomoses may represent an improvement over traditional hand-sewn or stapled techniques. This prospective exploratory study aimed to assess the efficacy and complication rates in patients undergoing anterior resection (AR) or low anterior resection (LAR) anastomosed with a novel end-to-end compression anastomosis ring, the ColonRing.

METHODS

In all, 20 patients (13 male) undergoing AR or LAR were enrolled to be anastomosed using the NiTi Shape Memory End-to-End Compression Anastomosis Ring (NiTi Medical Technologies Ltd, Netanya, Israel). Demographic, intraoperative, and postoperative data were collected.

RESULTS

Patients underwent AR (11/20) or LAR using laparoscopy (75%), robotic (10%) surgery, or an open laparotomy (15%) approach, with a median anastomotic level of 14.5 cm (range, 4-25 cm). Defunctioning loop ileostomies were formed in 6 patients for low anastomoses. Surgeons rated the ColonRing device as either easy or very easy to use. One patient developed an anastomotic leakage in the early postoperative period; there were no late postoperative complications. Mean time to passage of first flatus and commencement of oral fluids was 2.5 days and 3.2 days, respectively. Average hospital stay was 12.6 days (range, 8-23 days). Finally, the device was expelled on average 15.3 days postoperatively without difficulty.

CONCLUSIONS

This is the first study reporting results in a significant number of LAR patients and the first reported experience from South Korea; it shows that the compression technique is surgically feasible, easy to use, and without significant complication rates. A large randomized controlled trial is warranted to investigate the benefits of the ColonRing over traditional stapling techniques.

Colonic ischemia following surgery for sigmoid colon and rectal cancer: a study of 10 cases and a review of the literature

PURPOSE

Colonic ischemia following colorectal surgery is an unusual and serious complication. As it has been reported that the incidence of colonic ischemia was higher after laparoscopic surgery, the aim of this report was to document the clinical features of postoperative colonic ischemia following colorectal surgery.

METHODS

Among 1,201 surgeries for sigmoid colon and rectal cancer by a single surgeon from 2006 to 2010, 10 cases of postoperative colonic ischemia were retrospectively identified (0.83%). IMA high ligation was routinely made in all surgeries. The clinical findings and laboratory data of these 10 cases were evaluated.

RESULTS

Of the 10 patients, 9 were male and 1 was female. The mean age was 66.9 years old. The mean BMI was 23.3. Three patients (30%) had a cardiovascular disease other than hypertension. Eight patients (80%) underwent laparoscopic surgery and two patients (20%) underwent open surgery. Intraoperative bleeding occurred in five patients (50%, mean 435 ml). The average day for occurrence of postoperative colonic ischemia was on the 5th day (range 2nd-10th day). A consistent postoperative fever was found in eight patients (80%). Mortality due to postoperative colonic ischemia was 10%.

CONCLUSIONS

Postoperative colonic ischemia may be considered one of the more important complications of colorectal resection.

Pretreatment of polyethylene terephthalate substrate for the growth of Ga-doped ZnO thin film

The effect of the pretreatment of polyethylene terephthalate (PET) substrate on the growth of transparent conducting Ga-doped ZnO (GZO) thin film was investigated. Because of its high gas and moisture absorption and easy gas permeation, PET substrate was annealed at 100 degrees C in a vacuum chamber prior to the sputtering growth of GZO thin film for the outgassing of impurity gases. GZO thin film was deposited on the pretreated PET substrate by rf-magnetron sputtering and significantly improved electrical properties of GZO thin film was achieved. Electrical and structural characterizations of the GZO thin films were carried out by 4-point probe, Hall measurement, and scanning electron microscopy, and the effects of the pretreatment on the improved properties of GZO thin films were discussed. This result is not only useful to PET substrate, but also could be applicable to other plastic substrates which inevitably containing the moisture and impurity gases.

Expression of transforming growth factor-beta1 and hypoxia-inducible factor-1alpha in renal transplantation

Chronic allograft nephropathy (CAN) includes pathologic changes of interstitial fibrosis, tubular atrophy, and fibrous intimal thickening. Transforming growth factor (TGF)-beta1 is a fibrogenic cytokine involved in renal allograft fibrosis. Hypoxia-inducible factor (HIF)-1alpha is induced as an adaptive response to hypoxia triggering the production of fibrogenic cytokines such as TGF-beta1. Between January 1995 and February 2005, we performed 71 renal allograft biopsies in 61 recipients. Immunohistochemical studies were performed with an immunoperoxidase technique using as the primary antibody either a rabbit anti-human TGF-beta1 polyclonal or a mouse anti-human HIF-1alpha monoclonal reagent. The glomerular TGF-beta1 expression in recipients diagnosed with glomerulonephritis was significantly greater than other pathologic groups (P < .05), and the glomerular TGF-beta1 expression in the heavy proteinuria group (> or =2.5 g/d) was significantly greater than the low proteinuria group (<1.0 g/d; P < .05). The tubular and interstitial TGF-beta1 and HIF-1alpha expressions in CAN were greater than in other groups (P < .05). The tubular TGF-beta1 expression among the graft loss group was significantly greater than the graft function group (P < .05).

Nutrient removal processes for low strength wastewater

For nutrient removal from low strength wastewater, biological nutrient removal (BNR) processes available at present are not efficient due to the shortage of organic carbon. By using the carbon source obtained from the degradation of return sludge, it was attempted to enhance the efficiency of denitrification and phosphorus release. Based on its degradation mechanism, the ENR (Endogenous Nitrate Respiration) process was developed and compared with the conventional A2/O (Anaerobic/Anoxic/Aerobic), MUCT (Modified University of Cape Town) processes. In the experiment, the specific phosphorus release rates of A2/O, MUCT, and ENR processes were 0.8, 2.3, and 2.6 mg PO1-P g1 MLVSS-h. As the nitrate concentration decreased below 3.0 mg NO1-N l1 due to the endogenous nitrate respiration, the effluent nitrate of the ENR process was lower than the A2/O process and the MUCT process by 25% and 10% while the phosphorus removal efficiencies increased by 15% and 6%, respectively. It was found that the ENR process was an effective and economical alternative for removing nutrient from low strength wastewater

Effect of ouabain on relaxation induced by cromakalim in human and canine mesenteric arteries

We investigated the effect of cromakalim, a K+ channel opener, that activates indirectly the Na(+)-K+ pump, in association with increased K+ conductance in the mesenteric arteries. In 65% of human mesenteric arteries tested, the concentration-dependent relaxation curves for cromakalim were biphasic: the low concentration (< 10(-7) M) effect was preferentially inhibited by ouabain, whereas the higher concentration effect was significantly inhibited by glibenclamide. In branches of canine mesenteric artery, the cromakalim-induced relaxation was inhibited by pretreatment with ouabain (1 microM) as well as by glibenclamide (1 microM). The reduction in contraction of human and canine mesenteric arterial strips caused by cromakalim was totally reversed by pretreatment with ouabain (1 microM) or glibenclamide (1 microM). On the other hand, in canine mesenteric artery, cromakalim caused a significant stimulation of 22Na+ influx and ouabain-sensitive 86Rb+ uptake in association with increased 86Rb+ efflux, all of which were inhibited by glibenclamide (1 microM). Thus, it is suggested that cromakalim possesses the additional property to stimulate the Na(+)-K+ pump through an elevation in intracellular Na+, resulting in strong relaxation of blood vessels.

Pseudoexfoliation syndrome--case report and review of clinical features

Pseudoexfoliation syndrome is characterized by the presence of gray-white flakes on the pupillary borders and anterior lens capsule, increased trabecular meshwork pigmentation, and association with glaucoma. We describe 3 patients with this syndrome seen at Asan Meidcal Center Department of Ophthalmology in 1989, and we focus on their clinical features and management. We believe that patients with this syndrome are not as rare in Korea as has been thought, judging by scant report of cases in the past.

Structure of 3-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-triazole

C15H13N3O, Mr = 251.29, triclinic, P-1, a = 9.294, (1), b = 11.394 (4), c = 13.375 (2) A, a = 103.60 (2), beta = 96.82 (1), gamma = 107.47 (2) degrees, V = 1285 A3, Z = 4, Dx = 1.30 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.92 cm-1, F(000) = 528, T = 295 K, final R = 0.045 for 2311 observed [Fo greater than or equal to 5 sigma(Fo)] reflections. There are two molecules in the asymmetric unit. The triazole rings are planar with the phenyl substituents twisted with respect to these planes. The two molecules in the asymmetric unit are different in the relative twists of the phenyl groups.