Alum-tuned hyaluronic acid-based hydrogel with immune checkpoint inhibition for immunophoto therapy of cancer

Alum-crosslinked hyaluronic acid-dopamine (HD) hydrogel containing indocyanine green (ICG) with anti-programmed cell death-1 (PD-1) antibody (Ab) administration was developed for immunophoto therapy of cancer. Alum modulates the rheological characteristics of hydrogel for enabling syringe injection, shear-thinning feature, and slower biodegradation. In addition, alum in HD-based hydrogel provided CD8+ T cell-mediated immune responses for cancer therapy. ICG in the hydrogel under near-infrared (NIR) light exposure may induce hyperthermia and generate singlet oxygen for selective cancer cell killing. HD/alum/ICG hydrogel injection with NIR laser irradiation elevated PD-1 level in CD8+ T cells. Administration of PD-1 Ab aiming at highly expressed PD-1 in T cells may amplify the anticancer efficacies of HD/alum/ICG hydrogel along with NIR laser. HD/alum/ICG hydrogel with NIR light may have both CD8+ T cell-linked immune responses and ICG-related photodynamic/photothermal effects. Additional injection of immune checkpoint inhibitor can ultimately suppress primary and distant tumor growth by combination with those therapeutic actions.

Polyhydroxybutyrate (PHB) production from sugar cane molasses and tap water without sterilization using novel strain, Priestia sp. YH4

The production cost of biodegradable polymer like polyhydroxybutyrate (PHB) is still higher than that of petroleum-based plastics. A potential solution for reducing its production cost is using a cheap carbon source and avoiding a process of sterilization. In this study, a novel PHB-producing microbial strain, Priestia sp. YH4 was screened from the marine environment using sugarcane molasses as the carbon source without sterilization. Culture conditions, such as carbon, NaCl, temperature, pH, inoculum size, and cultivation time, were optimized for obtaining the highest PHB production by YH4 resulting in 5.94 g/L of dry cell weight (DCW) and 61.7 % of PHB content in the 5 mL culture. In addition, it showed similar PHB production between the cultures with or without sterilization in Marine Broth media. When cultured using only tap water, sugarcane molasses, and NaCl in a 5 L fermenter, 24.8 g/L DCW was produced at 41 h yielding 13.9 g/L PHB. Finally, DSC (Differential Scanning Calorimetry) and GPC (Gel Permeation Chromatography) were used to analyze thermal properties and molecular weights resulting in Tm = 167.2 °C, Tc = 67.3 °C, Mw = 2.85 × 105, Mn = 1.05 × 105, and PDI = 2.7, respectively. Therefore, we showed the feasibility of more economical process for PHB production by finding novel strain, utilizing molasses with minimal media components and avoiding sterilization.

Definitive Radiotherapy in Patients with Clinical T1N0M0 Esophageal Squamous Cell Carcinoma: A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

In this study, we aimed to assess the failure pattern and survival outcomes and to analyze the optimal treatment field of definitive RT for T1N0M0 esophageal squamous cell carcinoma (ESCC).

MATERIALS/METHODS

We performed a retrospective analysis in a multi-institutional cohort of patients with histologically confirmed T1N0M0 ESCC. We included patients who underwent RT with definitive aim from 2010 to 2019. Patterns of failure were demonstrated as in-field locoregional, out-field locoregional and distant metastasis. In the survival analysis, freedom from locoregional recurrence and their association with clinicopathologic risk factors were analyzed. We performed a propensity score matching in the cT1b patients to adjust for the heterogeneity of radiation technique, radiation dose and the use of concurrent chemotherapy.

RESULTS

A total of 168 patients were included with a median follow-up of 34.0 months, and there were 20 cT1a, 94 cT1b and 24 cT1x, (cT1, not otherwise specified) patients. The rates of all and locoregional failure were 26.9% and 23.1% for cT1a and 25.0% and 22.4% for cT1b patients. 10 (10.6%) patients experienced grade ≥ 3 adverse events. Among 116 cT1b patients, 69 patients received elective nodal irradiation (ENI) and 47 patients received involved field irradiation (IFI). After propensity score matching, the 3-year FFLRR rate was 84.5% (95% Confidence Interval, 71.0 - 92.1%). There was no significant difference between the ENI and IFI patients in FFLRR (Log-rank P = 0.831). In the multivariate analysis, the use of concurrent chemotherapy was the only factor marginally associated with FFLRR (Hazard ratio, 0.17; 95% CI, 0.02 - 1.13; P = 0.067).

CONCLUSION

cT1a patients who cannot receive endoscopic resection, showed similar rates of failure compared with cT1b patients, which questioned the accuracy of the staging and raised the need for through treatment such as chemoradiotherapy. In cT1b patients, IFI using dose of 50 to 60 Gy with concurrent chemotherapy could be a reasonable treatment option.

Treatment Outcomes of Stereotactic Body Radiation Therapy for Pulmonary Metastasis from Sarcoma: A Multicenter, Retrospective Study

PURPOSE/OBJECTIVE(S)

The aim of this study was to evaluate the treatment outcomes and potential dose-response relationship of stereotactic body radiation therapy (SBRT) for pulmonary metastasis of sarcoma.

MATERIALS/METHODS

A retrospective review of 39 patients and 71 lesions treated with SBRT from two institutions was performed. The patients had oligometastatic or oligoprogressive disease, or were receiving palliation. Doses of 20-60 Gy were delivered in 1-5 fractions. The local control per tumor (LCpT) was evaluated according to the biologically effective dose with an α/β ratio of 10 (BED10) of the prescribed dose (BED10 ≥ 100 Gy vs. BED10 < 100 Gy). Clinical outcomes per patient, including local control per patient (LCpP), pulmonary progression-free rate (PPFR), any progression-free rate (APFR), and overall survival (OS) were investigated.

RESULTS

The median follow-up period was 27.2 months. The 1-, 2-, and 3-year LCpT rates for the entire cohort were 100.0%, 88.3%, and 73.6%, respectively. There was no observed difference in LCpT between the two BED10 groups (p = 0.180). The 3-year LCpP, PPFR, APFR, and OS rates were 78.1%, 22.7%, 12.9%, and 83.7%, respectively. Five (12.8%) patients with oligometastasis had long-term disease-free intervals, with a median survival period of 40.7 months. Factors that were associated with a worse prognosis were oligoprogression (vs. oligometastasis), multiple pulmonary metastases, and simultaneous extrathoracic metastasis.

CONCLUSION

SBRT for pulmonary metastasis of sarcoma is effective. Some selected patients may achieve durable response. Considerations of SBRT indication and disease extent may be needed as they may influence the prognosis.

Ocular Surface and Tear Cytokine Changes after Cataract Surgery in Patients with Type 2 Diabetes

PURPOSE

To evaluate changes in ocular surface indices and tear cytokines after cataract surgery in type 2 diabetic patients.

METHODS

Ocular surface indices and concentrations of tear cytokines (MCP-1, IL-6, IL-8, and VEGF) were evaluated at baseline and one week and one month postoperatively.

RESULTS

Patients (30 diabetic and 30 control) were enrolled. In the diabetic group, changes in ocular symptom and tear breakup time remained until one month postoperatively (P < .05, respectively); in the control group, ocular symptom increased at one week postoperatively (P = .015). MCP-1 level in the diabetic group significantly increased postoperatively (all P < .05); however, in the control group, the IL-8 level was significantly decreased postoperatively (all P < .05). MCP-1 concentration was negatively correlated with TBUT in the diabetic group.

CONCLUSION

Diabetic patients can experience more prominent changes after surgery and these changes were accompanied by an increase of several tear cytokines.

The Early and Late Effects of High-Dose Irradiation on Cardiac Injury in a Rat Model

PURPOSE/OBJECTIVE(S)

Radiation-induced heart disease is a critical concern after radiotherapy (RT) for thoracic and chest wall tumors; however, the biological effects and mechanisms are still unknown. In this study, we investigated dose-responsive functional and pathological changes in rat hearts at 1, 3, and 5 months after high-dose irradiation. Then, we sought to elucidate the underlying mechanisms of myocardial changes induced by high-dose irradiation.

MATERIALS/METHODS

Whole hearts of rats (N = 72) were irradiated with a single fraction of 0 (control), 10, 20, or 30 Gy and allocated into three groups according to the follow-up period after RT: baseline, one, three, and five months. During follow-up periods, rats underwent functional evaluation by electrocardiogram and echocardiography at 4-week intervals. If a rat's body weight decreased by 20% or more, it was considered premature death, and the heart was explanted immediately. Otherwise, all hearts were explanted when each group's follow-up period was completed. Pathological changes of cardiac structures were evaluated using a light microscope after staining with hematoxylin-eosin, Masson's trichrome, α-smooth muscle actin, desmin, and connexin-43.

RESULTS

All rats irradiated with 0 or 10 Gy completed their follow-up periods with continuously increasing body weight. However, among rats irradiated with 20 or 30 Gy, half of the rats died prematurely at 8-10 weeks after RT, and the remainder survived until 20 weeks. In echocardiography, increased wall thickness and E/E' ratio, and decreased end-diastolic volume were observed in 20-30 Gy groups compared to 0-10 Gy groups from 8 weeks after RT. Ejection fraction was preserved in all groups. In pathological review, 20-30 Gy groups demonstrated diffuse inflammation and vacuolization at 4 weeks. Then, at 8 weeks, prominent fibrotic changes and intercalated disc disruptions were observed. Notably, fibrotic changes were somewhat resolved at 20 weeks, but intercalated disc disruptions were not repaired until 20 weeks. The 0 and 10 Gy groups showed no significant changes in both functional and pathological analyses.

CONCLUSION

Rats irradiated with 20 or 30 Gy showed diastolic dysfunction in functional analysis and time-dependent myocardial changes in pathological analysis. Radiation-induced fibrosis might be a "reactive" fibrosis, which could proceed to either a profibrotic course (progressive fibrosis) or an anti-fibrotic course (recovery phase). Further studies are needed to identify whether high-dose irradiation-induced cardiac fibrosis could be reversible.

Complementation of reducing power for 5-hydroxyvaleric acid and 1,5-pentanediol production via glucose dehydrogenase in Escherichia coli whole-cell system

One of the key intermediates, 5-hydroxyvaleric acid (5-HV), is used in the synthesis of polyhydroxyalkanoate monomer, δ-valerolactone, 1,5-pentanediol (1,5-PDO), and many other substances. Due to global environmental problems, eco-friendly bio-based synthesis of various platform chemicals and key intermediates are socially required, but few previous studies on 5-HV biosynthesis have been conducted. To establish a sustainable bioprocess for 5-HV production, we introduced gabT encoding 4-aminobutyrate aminotransferase and yqhD encoding alcohol dehydrogenase to produce 5-HV from 5-aminovaleric acid (5-AVA), through glutarate semialdehyde in Escherichia coli whole-cell reaction. As, high reducing power is required to produce high concentrations of 5-HV, we newly introduced glucose dehydrogenase (GDH) for NADPH regeneration system from Bacillus subtilis 168. By applying GDH with D-glucose and optimizing the parameters, 5-HV conversion rate from 5-AVA increased from 47% (w/o GDH) to 82% when using 200 mM (23.4 g/L) of 5-AVA. Also, it reached 56% conversion in 2 h, showing 56 mM/h (6.547 g/L/h) productivity from 200 mM 5-AVA, finally reaching 350 mM (41 g/L) and 14.6 mM/h (1.708 g/L/h) productivity at 24 h when 1 M (117.15 g/L) 5-AVA was used. When the whole-cell system with GDH was expanded to produce 1,5-PDO, its production was also increased 5-fold. Considering that 5-HV and 1,5-PDO production depends heavily on the reducing power of the cells, we successfully achieved a significant increase in 5-HV and 1,5-PDO production using GDH.

Comparisons of Psycho-Behavioral Factors, Body Composition, and Clinical Outcomes in Adults With Type 2 Diabetes by Perceived Hypoglycemia

PURPOSE

The purpose of the study was to examine the associations between perceived hypoglycemia and psycho-behavioral and clinical factors in persons with type 2 diabetes (T2D).

METHODS

Adults with T2D were recruited from outpatient clinics in a university hospital in Korea. Sociodemographics, psycho-behavioral and clinical factors, and body composition were assessed. The participants were divided into 2 groups reporting perceived hypoglycemia or not in the previous month based on an item of the Control Problem Scale. Group differences were compared at α = .05 using SPSS (version 26.0).

RESULTS

Of 177 participants, approximately one-third (n = 67) perceived hypoglycemia. The hypoglycemia group reported poor health-related quality of life, frequent blood monitoring and foot care, and sleep difficulties. However, no differences between groups were identified for diet, exercise, or glycosylated hemoglobin. The hypoglycemia group had a lower body mass index and a trend toward a lower skeletal muscle mass and fat free mass.

CONCLUSIONS

Perceived hypoglycemia was associated with psycho-behavioral factors and body composition. Importantly, some persons on oral antidiabetic medications that do not cause hypoglycemia still perceived hypoglycemia. Further investigation is warranted to examine the efficacy of strategies to minimize hypoglycemia and inappropriate fear of hypoglycemia. In addition, clinicians should be aware of the potential risk of hypoglycemia in persons with lower muscle mass.

A strategy to promote the convenient storage and direct use of polyhydroxybutyrate-degrading Bacillus sp. JY14 by lyophilization with protective reagents

BACKGROUND

Bioplastics are attracting considerable attention, owing to the increase in non-degradable waste. Using microorganisms to degrade bioplastics is a promising strategy for reducing non-degradable plastic waste. However, maintaining bacterial viability and activity during culture and storage remains challenging. With the use of conventional methods, cell viability and activity was lost; therefore, these conditions need to be optimized for the practical application of microorganisms in bioplastic degradation. Therefore, we aimed to optimize the feasibility of the lyophilization method for convenient storage and direct use. In addition, we incoporated protective reagents to increase the viability and activity of lyophilized microorganisms. By selecting and applying the best protective reagents for the lyophilization process and the effects of additives on the growth and PHB-degrading activity of strains were analyzed after lyophilization. For developing the lyophilization method for protecting degradation activity, it may promote practical applications of bioplastic-degrading bacteria.

RESULTS

In this study, the polyhydroxybutyrate (PHB)-degrading strain, Bacillus sp. JY14 was lyophilized with the use of various sugars as protective reagents. Among the carbon sources tested, raffinose was associated with the highest cell survival rate (12.1%). Moreover, 7% of raffionose showed the highest PHB degradation yield (92.1%). Therefore, raffinose was selected as the most effective protective reagent. Also, bacterial activity was successfully maintained, with raffinose, under different storage temperatures and period.

CONCLUSIONS

This study highlights lyophilization as an efficient microorganism storage method to enhance the applicability of bioplastic-degrading bacterial strains. The approach developed herein can be further studied and used to promote the application of microorganisms in bioplastic degradation.

Rewiring of Prelimbic Inputs to the Nucleus Accumbens Core Underlies Cocaine-Induced Behavioral Sensitization

BACKGROUND

Unbalanced activity of medium spiny neurons (MSNs) of the direct and indirect pathways mediates reward-related behaviors induced by addictive drugs. Prelimbic (PL) input to MSNs in the nucleus accumbens core (NAcC) plays a key role in cocaine-induced early locomotor sensitization (LS). However, the adaptive plastic changes at PL-to-NAcC synapses underlying early LS remain unclear.

METHODS

Using transgenic mice and retrograde tracing, we identified NAcC-projecting pyramidal neurons (PNs) in the PL cortex based on the expression of dopamine receptor types (D1R or D2R). To examine cocaine-induced alterations in PL-to-NAcC synapses, we measured excitatory postsynaptic current amplitudes evoked by optostimulation of PL afferents to MSNs. Riluzole was chosen to test the effects of PL excitability on cocaine-induced changes of PL-to-NAcC synapses.

RESULTS

NAcC-projecting PNs were segregated into D1R- and D2R-expressing PNs (D1- and D2-PNs, respectively), and their excitability was opposingly regulated by respective dopamine agonists. Both D1- and D2-PNs exhibited balanced innervation of direct MSNs and indirect MSNs in naïve animals. Repeated cocaine injections resulted in biased synaptic strength toward direct MSNs through presynaptic mechanisms in both D1- and D2-PNs, although D2R activation reduced the D2-PN excitability. Under group 1 metabotropic glutamate receptors coactivation, however, D2R activation enhanced the D2-PN excitability. The cocaine-induced rewiring accompanied LS, and both rewiring and LS were precluded by PL infusion of riluzole, which reduced the intrinsic excitability of PL neurons.

CONCLUSIONS

These findings indicate that cocaine-induced rewiring of PL-to-NAcC synapses correlates well with early behavioral sensitization and that rewiring and LS can be prevented by riluzole-induced reduction of excitability of PL neurons.

2023 Clinical Practice Guidelines for Diabetes Mellitus of the Korean Diabetes Association

In May 2023, the Committee of Clinical Practice Guidelines of the Korean Diabetes Association published the revised clinical practice guidelines for Korean adults with diabetes and prediabetes. We incorporated the latest clinical research findings through a comprehensive systematic literature review and applied them in a manner suitable for the Korean population. These guidelines are designed for all healthcare providers nationwide, including physicians, diabetes experts, and certified diabetes educators who manage patients with diabetes or individuals at risk of developing diabetes. Based on recent changes in international guidelines and the results of a Korean epidemiological study, the recommended age for diabetes screening has been lowered. In collaboration with the relevant Korean medical societies, recently revised guidelines for managing hypertension and dyslipidemia in patients with diabetes have been incorporated into this guideline. An abridgment containing practical information on patient education and systematic management in the clinic was published separately.

Two Cases of Severe Complications Due to an Esophageal Fish Bone Foreign Body

Cases of foreign body ingestion are encountered relatively often in clinical settings; however, serious complications are rare. In such cases, mediastinal abscess due to esophageal perforation can become a life-threatening complication. We encountered two cases of severe complications due to an esophageal fish bone foreign body. The first case was a 40-year-old male with an intramural esophageal abscess due to a fish bone after eating fish five days before visiting the hospital. The patient underwent surgical treatment, but the esophageal abscess did not improve; so, the abscess was drained through endoscopic mucosal dissection, and the abscess improved. In the second case, a 64-year-old male, who had eaten fish three days before visiting the hospital, had esophageal perforation by a fish bone, and abscess formation in the mediastinum and the lesser sac in the abdominal cavity were observed. Although surgical treatment was performed, the intra-abdominal abscess formation was not controlled; so, percutaneous drainage (PCD) was inserted, and the abscess improved. Both patients were discharged without any complications. Here, we report two cases that were improved through surgical treatments and additional treatments such as endoscopic dissection and PCD.

GDF10 is related to obesity as an adipokine derived from subcutaneous adipose tissue

Introduction

Adipokines are proteins that are secreted by the adipose tissue. Although they are associated with obesity-related metabolic disorders, most studies have focused on adipokines expressed by visceral adipose tissue (VAT). This study aimed to identify the adipokine potentially derived from subcutaneous adipose tissue (SAT) and its clinical significance.

Methods

Samples of SAT and VAT were obtained from six adult male patients who underwent laparoscopic surgery for benign gall bladder disease. Differentially expressed genes were analyzed by subjecting the samples to RNA sequencing. The serum concentration of selected proteins according to body mass index (BMI) was analyzed in 58 individuals.

Results

GDF10 showed significantly higher expression in the SAT, as per RNA sequencing (fold change = 5.8, adjusted P value = 0.009). Genes related to insulin response, glucose homeostasis, lipid homeostasis, and fatty acid metabolism were suppressed when GDF10 expression was high in SAT, as per genotype-tissue expression data. The serum GDF10 concentration was higher in participants with BMI ≥ 25 kg/m² (n = 35, 2674 ± 441 pg/mL) than in those with BMI < 25 kg/m² (n = 23, 2339 ± 639 pg/mL; P = 0.022). There was a positive correlation between BMI and serum GDF10 concentration (r = 0.308, P = 0.019).

Conclusions

GDF10 expression was higher in SAT than in VAT. Serum GDF10 concentration was high in patients with obesity. Therefore, GDF10 could be a SAT-derived protein related to obesity.

Marchf6 E3 ubiquitin ligase critically regulates endoplasmic reticulum stress, ferroptosis, and metabolic homeostasis in POMC neurons

The metabolic prohormone pro-opiomelanocortin (POMC) is generally translocated into the endoplasmic reticulum (ER) for entry into the secretory pathway. Patients with mutations within the signal peptide (SP) of POMC or its adjoining segment develop metabolic disorders. However, the existence, metabolic fate, and functional outcomes of cytosol-retained POMC remain unclear. Here, we show that SP-uncleaved POMC is produced in the cytosol of POMC neuronal cells, thus inducing ER stress and ferroptotic cell death. Mechanistically, the cytosol-retained POMC sequesters the chaperone Hspa5 and subsequently accelerates degradation of the glutathione peroxidase Gpx4, a core regulator of ferroptosis, via the chaperone-mediated autophagy. We also show that the Marchf6 E3 ubiquitin ligase mediates the degradation of cytosol-retained POMC, thereby preventing ER stress and ferroptosis. Furthermore, POMC-Cre-mediated Marchf6-deficient mice exhibit hyperphagia, reduced energy expenditure, and weight gain. These findings suggest that Marchf6 is a critical regulator of ER stress, ferroptosis, and metabolic homeostasis in POMC neurons.

Interruption of imatinib in advanced gastrointestinal stromal tumor after prolonged imatinib maintenance in the absence of gross tumor lesions

BACKGROUND

Current guidelines recommend indefinite imatinib treatment for advanced gastrointestinal stromal tumor (GIST) patients. Imatinib-refractory progression-free survival (PFS) and overall survival were previously reported not to differ between GIST patients who interrupted imatinib and those who did not.

METHODS

Clinical outcomes of 77 consecutive patients with recurrent or metastatic GIST who interrupted imatinib treatment after maintaining years of imatinib treatment in the absence of gross tumor lesions were retrospectively analyzed. Associations between clinical factors and progression-free survival (PFS) following imatinib interruption were analyzed.

RESULTS

The median time from the absence of gross tumor lesions to imatinib interruption was 61.5 months. Since imatinib interruption, the median PFS was 19.6 months, and 4 patients (26.3%) remained progression-free for longer than 5 years. Among the patients who had progressive disease following the interruption, imatinib re-introduction led to an 88.6% objective response rate and a 100% disease control rate. Complete removal of the initial gross tumor lesion(s) and complete removal of the residual gross tumor lesion(s) by local treatment (vs. no local treatment or residual lesions after local treatment) were independently associated with favorable PFS.

CONCLUSION

Interruption of imatinib following prolonged maintenance in the absence of gross tumor lesions led to disease progression in the majority of cases. However, re-introduction of imatinib resulted in effective tumor control. Unmaintained remission seems to be possible in some patients with metastatic or recurrent GIST after a prolonged remission with imatinib if there is complete removal of any gross tumor lesions.

Npas4-mediated dopaminergic regulation of safety memory consolidation

Amygdala circuitry encodes associations between conditioned stimuli and aversive unconditioned stimuli and also controls fear expression. However, whether and how non-threatening information for unpaired conditioned stimuli (CS^-) is discretely processed remains unknown. The fear expression toward CS^- is robust immediately after fear conditioning but then becomes negligible after memory consolidation. The synaptic plasticity of the neural pathway from the lateral to the anterior basal amygdala gates the fear expression of CS^-, depending upon neuronal PAS domain protein 4 (Npas4)-mediated dopamine receptor D4 (Drd4) synthesis, which is precluded by stress exposure or corticosterone injection. Herein, we show cellular and molecular mechanisms that regulate the non-threatening (safety) memory consolidation, supporting the fear discrimination.

Revealing the key gene involved in bioplastic degradation from superior bioplastic degrader Bacillus sp. JY35

The use of bioplastics, which can alleviate environmental pollution caused by non-degradable bioplastics, has received attention. As there are many types of bioplastics, method that can treat them simultaneously is important. Therefore, Bacillus sp. JY35 which can degrade different types of bioplastics, was screened in previous study. Most types of bioplastics, such as polyhydroxybutyrate (PHB), (P(3HB-co-4HB)), poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate (PBS), and polycaprolactone (PCL), can be degraded by esterase family enzymes. To identify the genes that are involved in bioplastic degradation, analysis with whole-genome sequencing was performed. Among the many esterase enzymes, three carboxylesterase and one triacylglycerol lipase were identified and selected based on previous studies. Esterase activity using p-nitrophenyl substrates was measured, and the supernatant of JY35_02679 showed strong emulsion clarification activity compared with others. In addition, when recombinant E. coli was applied to the clear zone test, only the JY35_02679 gene showed activity in the clear zone test with bioplastic containing solid cultures. Further quantitative analysis showed 100 % PCL degradation at 7 days and 45.7 % PBS degradation at 10 days. We identified a gene encoding a bioplastic-degrading enzyme in Bacillus sp. JY35 and successfully expressed the gene in heterologous E. coli, which secreted esterases with broad specificity.

Terbium-Rose Bengal Coordination Nanocrystals-Induced ROS Production under Low-Dose X-rays in Cultured Cancer Cells for Photodynamic Therapy

X-ray-triggered scintillators (Sc) and photosensitizers (Ps) have been developed for X-ray-induced photodynamic therapy (X-PDT) to selectively destruct deep tissue tumors with a low X-ray dose. This study designed terbium (Tb)-rose bengal (RB) coordination nanocrystals (T-RBNs) by a solvothermal treatment, aiming to reduce photon energy dissipation between Tb³⁺ and RB and thus increase the reactive oxygen species (ROS) production efficiency. T-RBNs synthesized at a molar ratio of [RB]/[Tb] = 3 exhibited a size of 6.8 ± 1.2 nm with a crystalline property. Fourier transform infrared analyses of T-RBNs indicated successful coordination between RB and Tb³⁺. T-RBNs generated singlet oxygen (¹O₂) and hydroxyl radicals (^•OH) under low-dose X-ray irradiation (0.5 Gy) via scintillating and radiosensitizing pathways. T-RBNs produced ∼8-fold higher ROS amounts than bare RB and ∼3.6-fold higher ROS amounts than inorganic nanoparticle-based controls. T-RBNs did not exhibit severe cytotoxicity up to 2 mg/mL concentration in cultured luciferase-expressing murine epithelial breast cancer (4T1-luc) cells. Furthermore, T-RBNs were efficiently internalized into cultured 4T1-luc cells and induced DNA double strand damage, as evidenced by an immunofluorescence staining assay with phosphorylated γ-H₂AX. Ultimately, under 0.5 Gy X-ray irradiation, T-RBNs induced >70% 4T1-luc cell death via simultaneous apoptosis/necrosis pathways. Overall, T-RBNs provided a promising Sc/Ps platform under low-dose X-PDT for advanced cancer therapy.

Macroalgae as a source of sugar and detoxifier biochar for polyhydroxyalkanoates production by Halomonas sp. YLGW01 under the unsterile condition

Macroalgae (seaweed) is considered a favorable feedstock for polyhydroxyalkanoates (PHAs) production owing to its high productivity, low land and freshwater requirement, and renewable nature. Among different microbes Halomonas sp. YLGW01 can utilize algal biomass-derived sugars (galactose and glucose) for growth and PHAs production. Biomass-derived byproducts furfural, hydroxymethylfurfural (HMF), and acetate affects Halomonas sp. YLGW01 growth and poly(3-hydroxybutyrate) (PHB) production i.e., furfural > HMF > acetate. Eucheuma spinosum biomass-derived biochar was able to remove 87.9 % of phenolic compounds from its hydrolysate without affecting sugar concentration. Halomonas sp. YLGW01 grows and accumulates a high amount of PHB at 4 % NaCl. The use of detoxified unsterilized media resulted in high biomass (6.32 ± 0.16 g cdm/L) and PHB production (3.88 ± 0.04 g/L) compared to undetoxified media (3.97 ± 0.24 g cdm/L, 2.58 ± 0.1 g/L). The finding suggests that Halomonas sp. YLGW01 has the potential to valorize macroalgal biomass into PHAs and open a new avenue for renewable bioplastic production.

Case report of laryngeal infection by Clinostomum complanatum 24 days after ingestion of raw fish

RATIONALE

Clinostomum complanatum is a laryngeal fluke whose hosts include birds and mammals.[1] In humans, infection occurs accidentally during the consumption of raw freshwater fish.[1,2].

PATIENT CONCERNS

A 59-year-old female presented to our hospital with throat pain and globus sensation. The patient had been prescribed Proton Pump Inibitor for 3 weeks at another hospital. The patient continued the medication, but the discomfort persisted, and she was admitted to our hospital for further examination. The patient had eaten raw fish 24 days before, and the symptoms occurred after eating the raw fish. Endoscopy under sedation showed a fluke, with an approximate length of 8.0 mm and width of 3.2 mm, on the interaryepiglottic fold, with active motility on the mucosa.

DIAGNOSIS INTERVENTIONS

It was extracted from the larynx using biopsy forceps and identified as C complanatum.

OUTCOMES

After the fluke was removed, symptoms improved, and the patient was discharged. The globus symptoms completely resolved at the last follow-up visit.

LESSONS

To the best of our knowledge, this is an endoscopically diagnosed and treated case of human infection by C complanatum in Korea after the longest period of infection. This suggests that C complanatum can survive for up to 3 weeks or more in the gastrointestinal tract. Endoscopy is a useful tool for the diagnosis and treatment of patients with atypical extraesophageal symptoms who do not respond to Proton Pump Inibitors.

Tissue-growth-based synthetic tree generation and perfusion simulation

Biological tissues receive oxygen and nutrients from blood vessels by developing an indispensable supply and demand relationship with the blood vessels. We implemented a synthetic tree generation algorithm by considering the interactions between the tissues and blood vessels. We first segment major arteries using medical image data and synthetic trees are generated originating from these segmented arteries. They grow into extensive networks of small vessels to fill the supplied tissues and satisfy the metabolic demand of them. Further, the algorithm is optimized to be executed in parallel without affecting the generated tree volumes. The generated vascular trees are used to simulate blood perfusion in the tissues by performing multiscale blood flow simulations. One-dimensional blood flow equations were used to solve for blood flow and pressure in the generated vascular trees and Darcy flow equations were solved for blood perfusion in the tissues using a porous model assumption. Both equations are coupled at terminal segments explicitly. The proposed methods were applied to idealized models with different tree resolutions and metabolic demands for validation. The methods demonstrated that realistic synthetic trees were generated with significantly less computational expense compared to that of a constrained constructive optimization method. The methods were then applied to cerebrovascular arteries supplying a human brain and coronary arteries supplying the left and right ventricles to demonstrate the capabilities of the proposed methods. The proposed methods can be utilized to quantify tissue perfusion and predict areas prone to ischemia in patient-specific geometries.

Continuous production of gamma aminobutyric acid by engineered and immobilized Escherichia coli whole-cells in a small-scale reactor system

γ-Amino butyric acid (GABA) is a non-proteinogenic amino acid and a human neurotransmitter. Recently, increasing demand for food additives and biodegradable bioplastic monomers, such as nylon 4, has been reported. Consequently, considerable efforts have been made to produce GABA through fermentation and bioconversion. To realize bioconversion, wild-type or recombinant strains harboring glutamate decarboxylase were paired with the cheap starting material monosodium glutamate, resulting in less by-product formation and faster production compared to fermentation. To increase the reusability and stability of whole-cell production systems, this study used an immobilization and continuous production system with a small-scale continuous reactor for gram-scale production. The cation type, alginate concentration, barium concentration, and whole-cell concentration in the beads were optimized and this optimization resulted in more than 95 % conversion of 600 mM monosodium glutamate to GABA in 3 h and reuse of the immobilized cells 15 times, whereas free cells lost all activity after the ninth reaction. When a continuous production system was applied after optimizing the buffer concentration, substrate concentration, and flow rate, 165 g of GABA was produced after 96 h of continuous operation in a 14-mL scale reactor. Our work demonstrates the efficient and economical production of GABA by immobilization and continuous production in a small-scale reactor.

A practical approach for small bowel bleeding

Gastrointestinal (GI) bleeding is one of the most common conditions among patients visiting emergency departments in Korea. GI bleeding is divided into upper and lower GI bleeding, according to the bleeding site. GI bleeding is also divided into overt and occult GI bleeding based on bleeding characteristics. In addition, obscure GI bleeding refers to recurrent or persistent GI bleeding from a source that cannot be identified after esophagogastroduodenoscopy or colonoscopy. The small intestine is the largest part of the alimentary tract. It extends from the pylorus to the cecum. The small intestine is difficult to access owing to its long length. Moreover, it is not fixed to the abdominal cavity. When hemorrhage occurs in the small intestine, the source cannot be found in many cases because of the characteristics of the small intestine. In practice, small-intestinal bleeding accounts for most of the obscure GI bleeding. Therefore, in this review, we introduce and describe systemic approaches and examination methods, including video capsule endoscopy and balloon enteroscopy, that can be performed in patients with suspected small bowel bleeding in clinical practice.

Efficacy and Safety of Chemotherapy in Elderly Patients with Unresectable Pancreatic Cancer

BACKGROUND/AIMS

The incidence of pancreatic cancer (PC) is gradually increasing among elderly individuals, but there are insufficient clinical data on elderly individuals. To determine the efficacy and safety of chemotherapy, we compared the. the outcomes of elderly patients with unresectable PC.

METHODS

We enrolled patients aged 75 years or older diagnosed with PC from 1 January 2010 to 30 November 2021. Propensity score matching (PSM) was used to reduce the heterogeneity of the study population. For efficacy evaluation, the median overall survival (OS) was estimated for the chemotherapy and nonchemotherapy groups. Chemotherapy tolerability evaluations were also investigated.

RESULTS

The study included 115 patients, 47 of whom received chemotherapy and 68 who did not. After PSM, compared with the nonchemotherapy group, the chemotherapy group had more myocardial infarctions (14.6 vs. 0.0%, p < 0.001) and chronic obstructive pulmonary disease (4.4 vs. 0.0%, p = 0.043). The primary endpoint, median OS, was significantly different in the with vs. without chemotherapy groups (203 vs. 106 days, p = 0.013). In the chemotherapy group, 10 patients (21.3%) discontinued treatment due to adverse events. However, there were no reports of death due to severe adverse events.

CONCLUSIONS

This study demonstrated that chemotherapy improved median OS among elderly patients. These data could support the use of chemotherapy for elderly patients with unresectable PC.

Enhancement of biohydrogen production in Clostridium acetobutylicum ATCC 824 by overexpression of glyceraldehyde-3-phosphate dehydrogenase gene

In the dark fermentation of hydrogen, development of production host is crucial as bacteria act on substrates and produce hydrogen. The present study aimed to improve hydrogen production through the development of Clostridium acetobutylicum as a superior biohydrogen producer. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which produces NADH/NADPH for metabolites and energy in primary pathways, was introduced to enhance hydrogen production. The strain CAC824-G containing gapC that encodes GAPDH showed a 66.3 % higher hydrogen production than the wild-type strain, with increased NADH and NADPH pools. Glucose consumption and other byproducts, such as acetone, butanol, and ethanol, were also high in CAC824-G. Overexpression of gapC resulted in increased hydrogen production with sugars obtained from different biomass, even in the presence of inhibitors such as vanillin, 5-hydroxymethylfufural, acetic acid, and formic acid. Our results imply that overexpression of gapC in Clostridium is possible to expand the production of the reported biochemicals to produce hydrogen.

Clustered Microcysts Detected on Breast US in Asymptomatic Women

Purpose

To investigate the incidence, outcomes, and imaging characteristics of clustered microcysts detected on breast US in asymptomatic women, and suggest appropriate management guidelines.

Materials and Methods

We identified and reviewed the lesions recorded as "clustered microcysts" on breast US performed in asymptomatic women between August 2014 and December 2019. The final diagnosis was based on pathology and imaging follow-up results for at least 12 months.

Results

The incidence was 1.5% and 100 patients with 117 lesions were included. Among 117 lesions, 3 (2.6%), 2 (1.7%), and 112 (95.7%) were malignant, high-risk benign, and benign lesions, respectively. The malignant lesions included two cases of ductal carcinoma in situ and one invasive ductal carcinoma. Two of them were assessed as category 4, showing mammographic suspicious microcalcifications and internal vascularity on Doppler US. The remainder was a false negative case and showed echo pattern change on the 12-month follow-up US.

Conclusion

The incidence of clustered microcysts on breast US in asymptomatic women was 1.5% and malignancy rate was 2.6% (3 of 117). Knowledge of outcomes and imaging features of benign and malignant clustered microcysts may be helpful for radiologists, thereby aiding categorization and management recommendations.

Added Value of Structured Reporting for US of the Pediatric Appendix: Additional CT Examinations and Negative Appendectomy

Purpose

This study aimed to determine the incremental value of using a structured report (SR) for US examinations of the pediatric appendix.

Materials and Methods

Between January 2009 and June 2016, 1150 pediatric patients with suspected appendicitis who underwent US examinations of the appendix were included retrospectively. In November 2012, we developed a five-point scale SR for appendix US examinations. The patients were divided into two groups according to the form of the US report: free-text or SR. The primary clinical outcomes were compared between the two groups, including the rate of CT imaging following US examinations, the negative appendectomy rate (NAR), and the appendiceal perforation rate (PR).

Results

In total, 550 patients were included in the free-text group and 600 patients in the SR group. The rate of additional CT examinations decreased by 5.3% in the SR group (8.2%, p = 0.003), and the NAR decreased by 8.4% in the SR group (7.8%, p = 0.028). There was no statistical difference in the appendiceal PR (37.6% vs. 48.0%, p = 0.078).

Conclusion

The use of an SR to evaluate US examinations for suspected pediatric appendicitis results in lower CT use and fewer negative appendectomies without an increase in appendiceal PR.

Strategy for efficiently utilizing Escherichia coli cells producing isobutanol by combining isobutanol and indigo production systems

Isobutanol is a potential biofuel, and its microbial production systems have demonstrated promising results. In a microbial system, the isobutanol produced is secreted into the media; however, the cells remaining after fermentation cannot be used efficiently during the isobutanol recovery process and are discarded as waste. To address this, we aimed to investigate the strategy of utilizing these remaining cells by combining the isobutanol production system with the indigo production system, wherein the product accumulates intracellularly. Accordingly, we constructed E. coli systems with genes, such as acetolactate synthase gene (alsS), ketol-acid reductoisomerase gene (ilvC), dihydroxyl-acid dehydratase (ilvD), and alpha-ketoisovalerate decarboxylase gene (kivD), for isobutanol production and genes, such as tryptophanase gene (tnaA) and flavin-containing monooxygenase gene (FMO), for indigo production. This system produced isobutanol and indigo simultaneously while accumulating indigo within cells. The production of isobutanol and indigo exhibited a strong linear correlation up to 72 h of production time; however, the pattern of isobutanol and indigo production varied. To our knowledge, this study is the first to simultaneously produce isobutanol and indigo and can potentially enhance the economy of biochemical production.

Effects of dietary glycerol supplementation on meat quality, palatability, and lipid metabolism gene expression in the longissimus thoracis of Hanwoo steers

This study tested the hypothesis that dietary glycerol supplementation (GS) would affect growth of Hanwoo steers, beef marbling and palatability, and gene expression for lipid uptake and transport and lipogenesis in the longissimus thoracis (LT). Diets with or without 45.2 g daily glycerol supplementation/kg dry matter concentrate were tested in fourteen Hanwoo steers during a 16-week feeding trial. GS did not affect (P ≥ 0.40) the average daily gain or the gain-to-feed ratio. GS increased the LT marbling score (P = 0.01). GS enhanced (P ≤ 0.01) the sensory traits, including the flavor and overall acceptance of the LT. GS tended (0.05 < P ≤ 0.10) to upregulate mRNA levels of fatty acid translocase, lipoprotein lipase, and fatty acid binding protein 4 genes in the LT. These tendencies of upregulated expression of fatty acid uptake and cytosolic transport genes may, in part, contribute to the increased marbling by GS. The increased marbling degree caused by GS may improve palatability including the flavor and overall acceptance of the LT.

Current Progress in Gallium-based Liquid Metals for Combinatory Phototherapeutic Anticancer Applications

A variety of therapeutic approaches using liquid metal (LM) have been intensively investigated, due to its unique physico-chemical properties that include high surface tension, fluidity, shape deformability, thermal conductivity, and electrical conductivity. Among a series of LMs, the relatively lower toxicity and minimal volatility of gallium (Ga)-based LMs (GaLMs) enables their usage in a series of potential biomedical applications, especially implantable platforms, to treat multiple diseases. In addition, the highly efficient conversion of light energy into thermal or chemical energy via GaLMs has led to recent developments in photothermal and photodynamic applications for anticancer treatments. As attractive photothermal agents or photosensitizers, a systematic interpretation of the structural characteristics and photo-responsive behaviors of GaLMs is necessary to develop effective anticancer engineering applications. Therefore, the aim of this review is to provide a comprehensive summary of currently suggested GaLM-mediated photo-therapeutic cancer treatments. In particular, the review summarizes (1) surface coating techniques to form stable and multifunctional GaLM particulates, (2) currently investigated GaLM-mediated photothermal and photodynamic anticancer therapies, (3) synergistic efficacies with the aid of additional interventions, and (4) 3D composite gels embedded with GaLMs particles, to convey the potential technological advances of LM in this field.

Direct Monitoring of Membrane Fatty Acid Changes and Effects on the Isoleucine/ Valine Pathways in an ndgR Deletion Mutant of Streptomyces coelicolor

NdgR, a global regulator in soil-dwelling and antibiotic-producing Streptomyces, is known to regulate branched-chain amino acid metabolism by binding to the upstream region of synthetic genes. However, its numerous and complex roles are not yet fully understood. To more fully reveal the function of NdgR, phospholipid fatty acid (PLFA) analysis with gas chromatography-mass spectrometry (GC-MS) was used to assess the effects of an ndgR deletion mutant of Streptomyces coelicolor. The deletion of ndgR was found to decrease the levels of isoleucine- and leucine-related fatty acids but increase those of valine-related fatty acids. Furthermore, the defects in leucine and isoleucine metabolism caused by the deletion impaired the growth of Streptomyces at low temperatures. Supplementation of leucine and isoleucine, however, could complement this defect under cold shock condition. NdgR was thus shown to be involved in the control of branched-chain amino acids and consequently affected the membrane fatty acid composition in Streptomyces. While isoleucine and valine could be synthesized by the same enzymes (IlvB/N, IlvC, IlvD, and IlvE), ndgR deletion did not affect them in the same way. This suggests that NdgR is involved in the upper isoleucine and valine pathways, or that its control over them differs in some respect.

Polyhydroxybutyrate production from crude glycerol using a highly robust bacterial strain Halomonas sp. YLGW01

Petrochemical-based plastics are hardly biodegradable and a major cause of environmental pollution, and polyhydroxybutyrate (PHB) is attracting attention as an alternative due to its similar properties. However, the cost of PHB production is high and is considered the greatest challenge for its industrialization. Here, crude glycerol was used as a carbon source for more efficient PHB production. Among the 18 strains investigated, Halomonas taeanenisis YLGW01 was selected for PHB production due to its salt tolerance and high glycerol consumption rate. Furthermore, this strain can produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3 HV)) with 17 % 3 HV mol fraction when a precursor is added. PHB production was maximized through medium optimization and activated carbon treatment of crude glycerol, resulting in 10.5 g/L of PHB with 60 % PHB content in fed-batch fermentation. Physical properties of the produced PHB were analyzed, i.e., weight average molecular weight (6.8 × 10⁵), number average molecular weight (4.4 × 10⁵), and the polydispersity index (1.53). In the universal testing machine analysis, the extracted intracellular PHB showed a decrease in Young's modulus, an increase in Elongation at break, greater flexibility than authentic film, and decreased brittleness. This study confirmed that YLGW01 is a promising strain for industrial PHB production using crude glycerol.

A162 RARE PRESENTATION OF EXTRANODAL NK/T-CELL LYMPHOMA INVOLVING STOMACH AND EYE: CASE REPORT AND LITERATURE REVIEW

Background

Extranodal NK/T-cell lymphoma (ENKTL) is a rare and aggressive form of non-Hodgkin lymphoma. ENKTL are predominantly localized to nasal and upper aerodigestive sites, but extranasal involvement including gastrointestinal tract are rarely seen. Small and large intestines are primary sites of gastrointestinal ENKTL. Gastric involvements are exceedingly rare accounting for less than 5% of all gastrointestinal ENKTL.

Purpose

We present a literature review on gastrointestinal ENKTL and a case report of gastrointestinal bleed secondary to ENKTL involving stomach and left orbit.

Method

Case report and literature review.

Result(s)

33-year-old female was admitted to a tertiary hospital with 3-week history of epigastric pain and left periorbital swelling. Abdominal CT showed edema and thickening of gastric folds. Head CT showed grossly enlarged left lateral rectus muscle and periorbital soft tissue swelling suggestive of left orbital pseudotumor. Esophagogastroduodenoscopy revealed multifocal Forrest classification II-C ulcerations throughout her stomach and duodenum. Biopsies from stomach showed gastric mucosa with extensive infiltration by an atypical lymphoid cell population. Immunohistochemistry demonstrated high grade lymphoid cells with uniform expression of CD2, CD3, CD30, CD56, TIA1, perforin and granzyme B. EBV-encoded small RNA in-situ hybridization (EBER ISH) was strongly positive. Findings were consistent with gastric ENKTL. Left orbital biopsy revealed similar morphology and phenotypic features consistent with concurrent ENKTL involvement of her orbit. Patient was initiated on intravenous corticosteroids, but unfortunately developed hemorrhagic shock secondary to gastrointestinal bleeding from gastric ulcer and passed away.

Gastrointestinal ENKTL is a rare presentation of a rare disease. Gastric involvement is especially rare and described only in few case reports. Gastrointestinal ENKTL are often initially asymptomatic but can progress to abdominal pain, bleeding and even bowel perforation. Due its nonspecific clinical features and rarity, diagnosis can be difficult and requires careful examination by an experienced pathologist. This aggressive lymphoma is characterized by positive CD2, CD3, CD30, CD56, TIA, granzyme B, perforin and EBER ISH. Optimal treatment approach remains unclear due to lack of prospective clinical studies. Currently, treatment modalities used for other lymphomas including radiotherapy and non-anthracycline-based chemotherapy are used. Despite treatment, prognosis is grim with median overall survival period of 7-8 months.

Image

Conclusion(s)

We present a case of gastric and orbital ENKTL with gastric ulcer bleeding. Gastric ENKTL disease is a rare presentation of a rare disease. Due to non-specific clinical features, diagnosis is often difficult and relies on careful pathology examination by experienced pathologist. Prognosis is poor without optimal treatment approach due to rarity of disease and lack of validated data.

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INFLAMMATORY BOWEL DISEASES

MECHANISMS AND TREATMENTS

A135 ENDOSCOPIC SUBMUCOSAL DISSECTION OF GASTRIC ADENOMAS AND EARLY CARCINOMAS

Background

Management of gastric adenoma and early gastric cancer requires endoscopic resection. This can often be achieved with endoscopic mucosal resection (EMR), which has been shown to be effective with a good safety profile. One disadvantage of EMR is that it is often completed piecemeal, leading to indeterminant margins and higher rates of recurrences that require additional intervention. Endoscopic submucosal dissection (ESD) is a more advanced endoscopic resection technique that has been shown to be more effective than EMR at en-bloc resection. ESD requires high technical proficiency but it is becoming more widely available in western countries.

Purpose

The purpose of this study is to report on the outcomes and rates of complications of gastric ESD completed in a tertiary centre in British Columbia.

Method

All gastric ESD was completed by a senior therapeutic endoscopist who has previously received training in Japan. Retrospective data were collected on all gastric ESD procedures done in St. Paul’s Hospital from May 7th, 2015, when the procedure first became available, to Aug 30th, 2022. Inclusion criteria were all adults who have undergone ESD for resection of a gastric lesion. Exclusion criteria were patients younger than 18. Data collected included demographic variables, polyp characteristics, procedural outcomes, and complications.

Result(s)

A total of 49 ESD procedures were completed. The mean size of the resected lesions was 25.3 mm (range: 5 – 100 mm). Technical success, defined as successful resection of all polypoid tissue, was achieved in 48/49 procedures (98.0%). En bloc resection was achieved in 42/48 (87.5%) completed ESD. The rate of R0 resection was also 42/48 (87.5%). Curative resection, defined as technically successful ESD with an R0 margin and no lymphovascular invasion, was achieved in 41/49 (83.7%) of the cases. In our cohort, 8 patients had adenocarcinoma, 5 of which had a curative resection with no evidence of recurrence. None of the ESD resulted in any intra-procedural or delayed perforation. 5/49 (10.2%) patients had clinically significant post-endoscopic resection bleeding. Out of 37 patients that completed follow-up, 3 (8.1%) had recurrence, and all of them were managed endoscopically. 4/49 (8.2%) of patients required surgery post-ESD.

Conclusion(s)

In our cohort, ESD is an effective endoscopic resection modality for gastric lesions with a high rate of technical success and curative resection. Despite a deeper plane of resection versus other endoscopic resection modalities, its complication rate remains low. Although ESD requires high technical proficiency, its favorable outcomes along with low rates of complication make ESD highly feasible for the resection of gastric lesions. Further research will be needed to study the implementation and outcomes of

ESD in a western setting.

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A131 ENDOSCOPIC SUBMUCOSAL DISSECTION OF COLORECTAL ADENOMAS AND EARLY ADENOCARCINOMAS: OUTCOMES FROM BRITISH COLUMBIA

Background

Endoscopic resection is the standard of care for the management of colorectal polyps. Larger and more complex polyps require endoscopic mucosal resection (EMR). While complications have been low, EMR is often piecemeal, resulting in indeterminant margins and often a higher recurrence rate. Endoscopic submucosal dissection (ESD) is an advanced endoscopic resection technique with a higher rate of en bloc resection. While more data exist for the resection of gastric lesions with ESD, ESD is becoming more widely used in western countries for the resection of colorectal lesions.

Purpose

The purpose of this study is to report on the outcomes and rates of complications for colorectal ESD completed in a tertiary centre in British Columbia.

Method

All colorectal ESD was completed by a senior therapeutic endoscopist who has previously received training in Japan. Retrospective data were collected on all colorectal ESD procedures done in St. Paul’s Hospital from July 11th, 2016, when the procedure first became available, to Aug 30th, 2022. Inclusion criteria were all adults who have undergone ESD for resection of a colorectal lesion. Exclusion criteria were patients younger than 18. Data collected included demographic variables, polyp characteristics, procedural outcomes, and complications.

Result(s)

A total of 39 ESD procedures were completed. The mean size of the resected lesion was 30.4 mm (range: 5 – 60 mm). Technical success, defined as successful resection of all polypoid tissue, was achieved in 35/39 procedures (89.7%). En-bloc resection was achieved in 27/35 (77.1%) of the completed ESD. The rate of R0 resection was 22/35 (62.9%). Curative resection, defined as technically successful ESD with R0 margin and no lymphovascular invasion, was achieved in 23/39 (59.0%) of the cases and the majority of the patients with non-curative resection that underwent endoscopic surveillance had no recurrence on follow-up. In our cohort, 3/39 (7.7%) patients had adenocarcinoma. None of the ESD resulted in any intra-procedural or delayed perforation. 3/39 (7.7%) patients had clinically significant post-endoscopic resection bleeding. Out of 24 patients that completed follow-up, 4 (16.7%) had recurrence at the resection site that was managed endoscopically. 4/39 (10.3%) of patients required surgery post-ESD.

Conclusion(s)

In our cohort, ESD is an effective endoscopic resection modality for the management of colorectal adenomas and early adenocarcinoma with a high rate of technical success and low rates of complications. Although the rate of curative resection was low, most were the result of R1 or Rx resection and a majority of the follow-ups in this subgroup demonstrated no further recurrence. The rate of en bloc resection is high, especially given the average size of adenomas in this cohort. Although ESD requires high technical proficiency, its favorable outcomes and low complication rates make ESD highly feasible for the resection of colorectal lesions.

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The association between smoking, changes in smoking behavior, and acute pancreatitis: A population-based cohort study in Korea

BACKGROUND AND AIMS

In the Asian population, existing studies regarding the association between smoking and acute pancreatitis are few in number. The aim of this study was to investigate the incidence of acute pancreatitis according to smoking habits and smoking habit changes of the Korean population.

METHODS

We used clinical data from individuals (aged 20 years or older) who received health examinations arranged by the Korean National Health Insurance Service in 2009 (n = 4 238 822) or in 2009 and 2011 (n = 2 617 306). The incidence of acute pancreatitis was analyzed according to smoking status or smoking habit change reported by individuals during their health examination. Newly diagnosed acute pancreatitis was identified using claims data from baseline to the date of diagnosis or until December 31, 2018.

RESULTS

The risk of acute pancreatitis was significantly higher in current smokers compared with never-smokers regardless of age or sex. The adjusted hazard ratio (HR) of acute pancreatitis in current smokers increased according to the amount of smoking (HR 1.28; 95% confidence interval [CI], 1.12-1.45 in <10 cigarettes/day, HR 1.4; CI, 1.3-1.52 in 10-19 cigarettes/day, HR 1.66; CI, 1.55-1.78 in ≥20 cigarettes/day). The adjusted HR of acute pancreatitis in continuous smokers was 1.66 (CI, 1.53-1.8) compared with never-smokers and was higher than smokers who quit smoking (HR 1.34; CI, 1.17-1.54).

CONCLUSIONS

In this Korean population-based cohort study, smoking increased the incidence of acute pancreatitis in a dose-dependent manner, and smoking cessation helped decrease the incidence of acute pancreatitis.

A Nationwide Survey on Gastrointestinal Endoscopy Practice Patterns among Pediatric Endoscopists in South Korea

Purpose

Gastrointestinal (GI) endoscopy is an important tool for diagnosing and treating GI diseases in children. This study aimed to analyze the current GI endoscopy practice patterns among South Korean pediatric endoscopists.

Methods

Twelve members of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition developed a questionnaire. The questionnaire was emailed to pediatric gastroenterologists attending general and tertiary hospitals in South Korea.

Results

The response rate was 86.7% (52/60), and 49 of the respondents (94.2%) were currently performing endoscopy. All respondents were performing esophagogastroduodenoscopy, and 43 (87.8%) were performing colonoscopy. Relatively rare procedures for children, such as double-balloon enteroscopy (DBE) (4.1%), endoscopic retrograde cholangiopancreatography (ERCP) (2.0%), and endoscopic ultrasound (EUS) (2.0%), were only performed by pediatric gastroenterologists at very few centers, but were performed by adult endoscopists in most of the centers; of all the respondents, 83.7% (41/49) performed emergency endoscopy. In most centers, the majority of the endoscopies were performed under sedation, with midazolam (100.0%) and ketamine (67.3%) as the most frequently used sedatives.

Conclusion

While most pediatric GI endoscopists perform common GI endoscopic procedures, rare procedures, such as DBE, ERCP, and EUS, are only performed by pediatric gastroenterologists at very few centers, and by adult GI endoscopists at most of the centers. For such rare procedures, close communication and cooperation with adult GI endoscopists are required.

Risk factors for delirium among patients with advanced cancer in palliative care: a multicenter, patient-based registry cohort in South Korea

OBJECTIVE

Previous studies have comprehensively investigated the prevalence and various potential risk factors for delirium among patients with advanced cancer admitted to the acute palliative care unit (APCU). Our objective was to evaluate the comprehensive association between delirium and various risk factors among patients with advanced cancer in an acute palliative care setting using a patient-based multicenter registry cohort.

PATIENTS AND METHODS

We performed a multicenter, patient-based registry cohort study collected in South Korea between January 1, 2019, and December 31, 2020. Delirium was identified using a medical record review based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

RESULTS

In total, 2,124 eligible patients with advanced cancer in the APCU met the inclusion criteria. There were 127 out of 2,124 patients (prevalence, 6.0%; 95% CI, 5.0 to 7.1) with delirium during admission. Delirium in patients with advanced cancer was associated with age >70 years (OR, 1.793; 95% CI, 1.246 to 2.581), male sex (OR, 1.675; 95% CI, 1.131 to 2.479), no chemotherapy during hospitalization (OR, 2.019; 95% CI, 1.236 to 3.298), hearing impairment (OR, 3.566; 95% CI, 1.176 to 10.810), underweight (OR, 1.826; 95% CI, 1.067 to 3.124), current use of opioid medication (OR, 1.942; 95% CI, 1.264 to 2.982), previous history of delirium (OR, 12.497; 95% CI, 6.920 to 22.568), and mental illness (OR, 2.333; 95% CI, 1.251 to 4.352).

CONCLUSIONS

In a large-scale multicenter patient-based registry cohort, delirium was associated with old age, male sex, no chemotherapy during hospitalization, hearing impairment, underweight, current use of opioid medication, and a history of delirium and mental illness. Our findings suggest physicians should pay attention to delirium in patients with advanced cancer admitted to the APCU with the above risk factors.

Enhanced production of bio-indigo in engineered Escherichia coli, reinforced by cyclopropane-fatty acid-acyl-phospholipid synthase from psychrophilic Pseudomonas sp. B14-6

Indigo dye is an organic compound with a distinctive blue color. Most of the indigo currently used in industry is produced via chemical synthesis, which generates a large amount of wastewater. Therefore, several studies have recently been conducted to find ways to produce indigo eco-friendly using microorganisms. Here, we produced indigo using recombinant Escherichia coli with both an indigo-producing plasmid and a cyclopropane fatty acid (CFA)-regulating plasmid. The CFA-regulating plasmid contains the cfa gene, and its expression increases the CFA composition of the phospholipid fatty acids of the cell membrane. Overexpression of cfa showed cytotoxicity resistance of indole, an intermediate product formed during the indigo production process. This had a positive effect on indigo production and cfa originated from Pseudomonas sp. B 14-6 was used. Optimal conditions for indigo production were determined by adjusting the expression strain, culture temperature, shaking speed, and isopropyl β-D-1-thiogalactopyranoside concentration. Treatment with Tween 80 at a particular concentration to increase the permeability of the cell membrane had a positive effect on indigo production. The strain with the CFA plasmid produced 4.1 mM of indigo after 24 h of culture and produced 1.5-fold higher indigo than the control strain without the CFA plasmid that produced 2.7 mM.

AI Improves Nodule Detection on Chest Radiographs in a Health Screening Population: A Randomized Controlled Trial

Background The impact of artificial intelligence (AI)-based computer-aided detection (CAD) software has not been prospectively explored in real-world populations. Purpose To investigate whether commercial AI-based CAD software could improve the detection rate of actionable lung nodules on chest radiographs in participants undergoing health checkups. Materials and Methods In this single-center, pragmatic, open-label randomized controlled trial, participants who underwent chest radiography between July 2020 and December 2021 in a health screening center were enrolled and randomized into intervention (AI group) and control (non-AI group) arms. One of three designated radiologists with 13-36 years of experience interpreted each radiograph, referring to the AI-based CAD results for the AI group. The primary outcome was the detection rate, that is, the number of true-positive radiographs divided by the total number of radiographs, of actionable lung nodules confirmed on CT scans obtained within 3 months. Actionable nodules were defined as solid nodules larger than 8 mm or subsolid nodules with a solid portion larger than 6 mm (Lung Imaging Reporting and Data System, or Lung-RADS, category 4). Secondary outcomes included the positive-report rate, sensitivity, false-referral rate, and malignant lung nodule detection rate. Clinical outcomes were compared between the two groups using univariable logistic regression analyses. Results A total of 10 476 participants (median age, 59 years [IQR, 50-66 years]; 5121 men) were randomized to an AI group (n = 5238) or non-AI group (n = 5238). The trial met the predefined primary outcome, demonstrating an improved detection rate of actionable nodules in the AI group compared with the non-AI group (0.59% [31 of 5238 participants] vs 0.25% [13 of 5238 participants], respectively; odds ratio, 2.4; 95% CI: 1.3, 4.7; P = .008). The detection rate for malignant lung nodules was higher in the AI group compared with the non-AI group (0.15% [eight of 5238 participants] vs 0.0% [0 of 5238 participants], respectively; P = .008). The AI and non-AI groups showed similar false-referral rates (45.9% [56 of 122 participants] vs 56.0% [56 of 100 participants], respectively; P = .14) and positive-report rates (2.3% [122 of 5238 participants] vs 1.9% [100 of 5238 participants]; P = .14). Conclusion In health checkup participants, artificial intelligence-based software improved the detection of actionable lung nodules on chest radiographs. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Auffermann in this isssue.

Deep brain stimulation by blood-brain-barrier-crossing piezoelectric nanoparticles generating current and nitric oxide under focused ultrasound

Deep brain stimulation via implanted electrodes can alleviate neuronal disorders. However, its applicability is constrained by side effects resulting from the insertion of electrodes into the brain. Here, we show that systemically administered piezoelectric nanoparticles producing nitric oxide and generating direct current under high-intensity focused ultrasound can be used to stimulate deep tissue in the brain. The release of nitric oxide temporarily disrupted tight junctions in the blood-brain barrier, allowing for the accumulation of the nanoparticles into brain parenchyma, and the piezoelectrically induced output current stimulated the release of dopamine by dopaminergic neuron-like cells. In a mouse model of Parkinson's disease, the ultrasound-responsive nanoparticles alleviated the symptoms of the disease without causing overt toxicity. The strategy may inspire the development of other minimally invasive therapies for neurodegenerative diseases.

A novel cardiac arrest severity score for the early prediction of hypoxic-ischemic brain injury and in-hospital death

Funding Acknowledgements

Type of funding sources: None.

Background

Out-of-hospital cardiac arrest (OHCA) outcomes are unsatisfactory despite postcardiac arrest care. Early prediction of prognoses might help stratify patients and provide tailored therapy.

Purpose

In this study, we derived and validated a novel scoring system to predict hypoxic-ischaemic brain injury (HIBI) and in-hospital death (IHD).

Methods

We retrospectively analysed Korean Hypothermia Network prospective registry data collected from in Korea between 2015 and 2018. Patients without neuroprognostication data were excluded, and the remaining patients were randomly divided into derivation and validation cohorts. HIBI was defined when at least one prognostication predicted a poor outcome. IHD meant all deaths regardless of cause. In the derivation cohort, stepwise multivariate logistic regression was conducted for HIBI and IHD scores, and model performance was assessed. We then classified patients into four categories and analysed associations between the categories and cerebral performance categories (CPCs) at hospital discharge. Finally, we validated our models in the internal validation cohort.

Results

Among 1373 patients, 240 were excluded, and 1133 were randomised into derivation (n=754) and validation cohorts (n=379). In the derivation cohort, 7 and 8 predictors were selected for HIBI (0–8) and IHD scores (0–11), respectively, and the area under the curve (AUC) was 0.85 (95% CI 0.82–0.87) and 0.80 (95% CI 0.77–0.82), respectively. Applying optimum cutoff values of ≥6 points for HIBI and ≥7 points for IHD, patients were classified as follows: HIBI (-)/IHD (-), Category 1 (n=424); HIBI (-)/IHD (+), Category 2 (n=100); HIBI (+)/IHD (-), Category 3 (n=21); and HIBI (+)/IHD (+), Category 4 (n=209). CPCs at discharge were significantly different in each category (p&lt;0.001). In the validation cohort, the model showed moderate discrimination (AUC 0.83, 95% CI 0.79–0.87 for HIBI and AUC 0.77, 95% CI 0.72–0.81 for IHD) with good calibration. Each category of the validation cohort showed a significant difference in discharge outcomes (p&lt;0.001) and a similar trend to the derivation cohort.

Conclusions

We presented a novel approach for assessing illness severity after OHCA. Although external prospective studies are warranted, risk stratification for HIBI and IHD could help provide OHCA patients with appropriate treatment.

Comparison of Horizontal White-to-white Diameter Measured Using Four Devices

Purpose: To compare the horizontal white-to-white (WTW) diameter measured using four devices.Methods: We measured the horizontal WTW diameter of 52 eyes of 52 patients using the IOL Master 500, ANTERION, OA-2000, and Pentacam HR devices. Repeated-measures analysis of variance was used to compare the measurements. Correlations between the measurements were evaluated using the Pearson correlation test. Agreement between measurements obtained using different instruments was confirmed using a Bland-Altman plot.Results: The mean horizontal WTW diameters obtained using IOL Master 500, ANTERION, OA-2000, and Pentacam HR were 11.65 ± 0.39, 11.52 ± 0.44, 11.51 ± 0.52, and 11.28 ± 0.41 mm, respectively. The horizontal WTW diameters obtained using IOL Master 500 and Pentacam HR were the largest and smallest, respectively. There was a statistically significant difference in mean diameter between IOL Master 500 and ANTERION (<i>p</i> = 0.03), as well as between Pentacam HR and the remaining three devices (all <i>p</i> < 0.001). There were positive correlations between the measurements obtained using the different devices (all r > 0.6, <i>p</i> < 0.001). The 95% limits of agreement between the measurements were 0.808-1.619 mm.Conclusions: There were statistically significant differences in horizontal WTW diameter between IOL Master 500 and ANTERION, and between IOL Master 500 and Pentacam HR, but not between IOL Master 500 and OA-2000. Measurements obtained using IOL Master 500 and the remaining three devices are not interchangeable because of their low level of agreement.

Association between Fiber Intake and Risk of Incident Chronic Kidney Disease: The UK Biobank Study

OBJECTIVES

Dietary fiber intake is associated with a lower risk of diabetes, cardiovascular disease, and cancer. However, it is unknown whether dietary fiber has a beneficial effect on preventing the development of chronic kidney disease (CKD).

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Using the UK Biobank prospective cohort, 110,412 participants who completed at least one dietary questionnaire and had an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, urinary albumin-to-creatinine ratio <30 mg/g, and no history of CKD were included. The primary exposure was total dietary fiber density, calculated by dividing the absolute amount of daily total fiber intake by total energy intake (g/1,000 kcal). We separately examined soluble and insoluble fiber densities as additional predictors. The primary outcome was incident CKD based on diagnosis codes.

RESULTS

A total of 3,507 (3.2%) participants developed incident CKD during a median follow-up of 9.9 years. In a multivariable cause-specific model, the adjusted hazard ratios (aHRs; 95% confidence intervals [CIs]) for incident CKD were 0.85 (0.77-0.94), 0.78 (0.70-0.86), and 0.76 (0.68-0.86), respectively, for the second, third, and highest quartiles of dietary fiber density (reference: lowest quartile). In a continuous model, the aHR for each +∆1.0g/1,000 kcal increase in dietary fiber density was 0.97 (95% CI, 0.95-0.99). This pattern of associations was similar for both soluble and insoluble fiber densities and did not differ across subgroups of sex, age, body mass index, hypertension, diabetes, smoking, and inflammation.

CONCLUSION

Increased fiber intake was associated with a lower risk of CKD in this large well-characterized cohort.

Proximal dendritic localization of NALCN channels underlies tonic and burst firing in nigral dopaminergic neurons

In multipolar nigral dopamine (DA) neurons, the highly excitable proximal dendritic compartments (PDCs) and two Na⁺ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. However, the causal link between them is unknown. Here we report that the proximal dendritic localization of NALCN underlies pacemaking and burst firing in DA neurons. Our morphological analysis of nigral DA neurons reveals that TRPC3 is ubiquitously expressed in the whole somatodendritic compartment, but NALCN is localized within the PDCs. Blocking either TRPC3 or NALCN channels abolished pacemaking. However, only blocking NALCN, not TRPC3, degraded burst discharges. Furthermore, local glutamate uncaging readily induced burst discharges within the PDCs, compared with other parts of the neuron, and NALCN channel inhibition dissipated burst generation, indicating the importance of NALCN to the high excitability of PDCs. Therefore, we conclude that PDCs serve as a common base for tonic and burst firing in nigral DA neurons. KEY POINTS: Midbrain dopamine (DA) neurons are slow pacemakers that can generate tonic and burst firings, and the highly excitable proximal dendritic compartments (PDCs) and two Na⁺ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. We find that slow tonic firing depends on the basal activity of both the NALCN and TRPC3 channels, but that burst firing does not require TRPC3 channels but relies only on NALCN channels. We find that TRPC3 is ubiquitously expressed in the entire somatodendritic compartment, but that NALCN exists only within the PDCs in nigral DA neurons. We show that NALCN channel localization confers high excitability on PDCs and is essential for burst generation in nigral DA neurons. These results suggest that PDCs serve as a common base for tonic and burst firing in nigral DA neurons.

Ciliated Foregut Cyst and Accessory Spleen in the Pancreas: A Case Report and Literature Review

Ciliated foregut cyst is a relatively rare disease; thus, most reports are in the form of case studies. This benign cyst is usually found in the mediastinum and account for approximately 20% of all mediastinal masses. However, it is rarely found in the hepatobiliary and peripancreatic regions. Approximately 20 cases of ciliated foregut cysts involving the pancreas have been reported in the Enlgish literature. Here, we present a case of ciliated foregut cyst that occurred in the tail of the pancreas in a 29-year-old female. The patient's ultrasonography, CT, and MRI findings are presented, along with a review of the literature.

Aqueous RAFT Polymerization-Induced Self-Assembly (PISA): Amphiphilic MacroRAFT Self-Assembly vs Monomer Droplet Nucleation (Miniemulsion Polymerization)

The effect of monomer droplet size on the particle formation mechanism in aqueous heterogeneous polymerization using a hydrophilic macroRAFT agent has been investigated. The specific system explored was the polymerization...

Randomised clinical trial: comparison of tegoprazan and lansoprazole as maintenance therapy for healed mild erosive oesophagitis

BACKGROUND

Tegoprazan is a novel potassium-competitive acid blocker used to treat acid-related disorders.

AIM

To compare tegoprazan 25 mg with lansoprazole 15 mg as maintenance therapy in healed erosive oesophagitis (EE) METHODS: In this phase 3, double-blind, multi-centre study, patients with endoscopically confirmed healed EE were randomised 1:1 to receive tegoprazan 25 mg or lansoprazole 15 mg once daily for up to 24 weeks. The primary efficacy endpoint was the endoscopic remission rate after 24 weeks. The secondary efficacy endpoint was the endoscopic remission rate after 12 weeks. Safety endpoints included adverse events, clinical laboratory results and serum gastrin and pepsinogen I/II levels.

RESULTS

We randomised patients to tegoprazan 25 mg (n = 174) or lansoprazole 15 mg (n = 177). Most had mild EE (Los Angeles (LA) grade A: 57.3%, LA grade B: 37.3%). The endoscopic remission rate after 24 weeks was 90.6% with tegoprazan and 89.5% with lansoprazole. Tegoprazan was not inferior to lansoprazole for maintaining endoscopic remission at 24 weeks and 12 weeks. In subgroup analysis, tegoprazan 25 mg showed no significant difference in maintenance rate according to LA grade (p = 0.47). The maintenance effect of tegoprazan was consistent in CYP2C19 extensive metabolisers (p = 0.76). Increases in serum gastrin were not higher in tegoprazan-treated than lansoprazole-treated patients.

CONCLUSIONS

Tegoprazan 25 mg was non-inferior to lansoprazole 15 mg in maintenance of healing of mild EE. In this study, tegoprazan had a similar safety profile to lansoprazole.

Radiomics Analysis of Magnetic Resonance Proton Density Fat Fraction for the Diagnosis of Hepatic Steatosis in Patients With Suspected Non-Alcoholic Fatty Liver Disease

BACKGROUND

This study aimed to assess the diagnostic feasibility of radiomics analysis based on magnetic resonance (MR)-proton density fat fraction (PDFF) for grading hepatic steatosis in patients with suspected non-alcoholic fatty liver disease (NAFLD).

METHODS

This retrospective study included 106 patients with suspected NAFLD who underwent a hepatic parenchymal biopsy. MR-PDFF and MR spectroscopy were performed on all patients using a 3.0-T scanner. Following whole-volume segmentation of the MR-PDFF images, 833 radiomic features were analyzed using a commercial program. Radiologic features were analyzed, including median and mean values of the multiple regions of interest and variable clinical features. A random forest regressor was used to extract the important radiomic, radiologic, and clinical features. The model was trained using 20 repeated 10-fold cross-validations to classify the NAFLD steatosis grade. The area under the receiver operating characteristic curve (AUROC) was evaluated using a classifier to diagnose steatosis grades.

RESULTS

The levels of pathological hepatic steatosis were classified as low-grade steatosis (grade, 0-1; n = 82) and high-grade steatosis (grade, 2-3; n = 24). Fifteen important features were extracted from the radiomic analysis, with the three most important being wavelet-LLL neighboring gray tone difference matrix coarseness, original first-order mean, and 90th percentile. The MR spectroscopy mean value was extracted as a more important feature than the MR-PDFF mean or median in radiologic measures. Alanine aminotransferase has been identified as the most important clinical feature. The AUROC of the classifier using radiomics was comparable to that of radiologic measures (0.94 ± 0.09 and 0.96 ± 0.08, respectively).

CONCLUSION

MR-PDFF-derived radiomics may provide a comparable alternative for grading hepatic steatosis in patients with suspected NAFLD.