Impact of mixed-infection rate of clarithromycin-susceptible and clarithromycin-resistant Helicobacter pylori strains on the success rate of clarithromycin-based eradication treatment.

BACKGROUND: Clarithromycin (CAM) resistance is a major contributor to the failure to eradicate Helicobacter pylori (H. pylori). The mixed-infection ratio of CAM-susceptible and CAM-resistant H. pylori strains differs among individuals. Pyrosequencing analysis can be used to quantify gene mutations at position each 2142 and 2143 of the H. pylori 23S rRNA gene in intragastric fluid samples. Herein, we aimed to clarify the impact of the rate of mixed infection with CAM-susceptible and CAM-resistant H. pylori strains on the success rate of CAM-containing eradication therapy. MATERIALS AND METHODS: Sixty-four H. pylori-positive participants who received CAM-based eradication therapy, also comprising vonoprazan and amoxicillin, were enrolled in this prospective cohort study. Biopsy and intragastric fluid samples were collected during esophagogastroduodenoscopy. H. pylori culture and CAM-susceptibility tests were performed on the biopsy samples, and real-time PCR and pyrosequencing analyses were performed on the intragastric fluid samples. The mutation rates and eradication success rates were compared. RESULTS: The overall CAM-based eradication success rate was 84% (54/64): 62% (13/21) for CAM-resistant strains, and 95% (39/41) for CAM-sensitive strains. When the mutation rate of the 23S rRNA gene was 20% or lower for both positions (2142 and 2143), the eradication success rate was 90% or more. However, when the mutation rate was 20% or higher, the eradication success rate was lower (60%). CONCLUSIONS: The mutation rate of the CAM-resistance gene was related to the success of eradication therapy, as determined via pyrosequencing analysis.

Lysoglycosphingolipids have the ability to induce cell death through direct PI3K inhibition.

Sphingolipidoses are inherited metabolic disorders associated with glycosphingolipids accumulation, neurodegeneration, and neuroinflammation leading to severe neurological symptoms. Lysoglycosphingolipids (lysoGSLs), also known to accumulate in the tissues of sphingolipidosis patients, exhibit cytotoxicity. LysoGSLs are the possible pathogenic cause, but the mechanisms are still unknown in detail. Here, we first show that lysoGSLs are potential inhibitors of phosphoinositide 3-kinase (PI3K) to reduce cell survival signaling. We found that phosphorylated Akt was commonly reduced in fibroblasts from patients with sphingolipidoses, including GM1/GM2 gangliosidoses and Gaucher's disease, suggesting the contribution of lysoGSLs to the pathogenesis. LysoGSLs caused cell death and decreased the level of phosphorylated Akt as in the patient fibroblasts. Extracellularly administered lysoGM1 permeated the cell membrane to diffusely distribute in the cytoplasm. LysoGM1 and lysoGM2 also inhibited the production of phosphatidylinositol-(3,4,5)-triphosphate and the translocation of Akt from the cytoplasm to the plasma membrane. We also predicted that lysoGSLs could directly bind to the catalytic domain of PI3K by in silico docking study, suggesting that lysoGSLs could inhibit PI3K by directly interacting with PI3K in the cytoplasm. Furthermore, we revealed that the increment of lysoGSLs amounts in the brain of sphingolipidosis model mice correlated with the neurodegenerative progression. Our findings suggest that the down-regulation of PI3K/Akt signaling by direct interaction of lysoGSLs with PI3K in the brains is a neurodegenerative mechanism in sphingolipidoses. Moreover, we could propose the intracellular PI3K activation or inhibition of lysoGSLs biosynthesis as novel therapeutic approaches for sphingolipidoses because lysoGSLs should be cell death mediators by directly inhibiting PI3K, especially in neurons.

Hepatocyte-specific damage in acute toxicity of sodium ferrous citrate: Presentation of a human autopsy case and experimental results in mice.

Acute iron overload is known to exert deleterious effects in the liver, but detailed pathology has yet to be documented. Here, we report pathological findings in an autopsy case of acute iron toxicity and validation of the findings in mouse experiments. In a 39-year-old woman who intentionally ingested a large amount of sodium ferrous citrate (equivalent to 7.5 g of iron), severe disturbance of consciousness and fulminant hepatic failure rapidly developed. Liver failure was refractory to treatment and the patient died on Day 13. Autopsy revealed almost complete loss of hepatocytes, while bile ducts were spared. To examine the detailed pathologic processes induced by excessive iron, mice were orally administered equivalent doses of ferrous citrate. Plasma aminotransferase levels markedly increased after 6 h, which was preceded by increased plasma iron levels. Hepatocytes were selectively damaged, with more prominent damage in the periportal area. Phosphorylated c-Jun was detected in hepatocyte nuclei after 3 h, which was followed by the appearance of γ-H2AX expression. Hepatocyte injury in mice was associated with the expression of Myc and p53 after 12 and 24 h, respectively. Even at lethal doses, the bile ducts were morphologically intact and fully viable. Our findings indicate that acute iron overload induces hepatocyte-specific liver injury, most likely through hydroxyl radical-mediated DNA damage and subsequent stress responses.

Mental workload during endoscopic sinus surgery is associated with surgeons' skill levels.

Introduction: Surgeons' mental workload during endoscopic sinus surgery (ESS) has not been fully evaluated. The assessment was challenging due to the great diversity of each patient's anatomy and the consequence variety of surgical difficulties. In this study, we examined the mental workload of surgeons with various surgical skill levels during ESS under the standardized condition provided by novel-designed 3D sinus models. Materials and methods: Forty-seven participants performed a high-fidelity ESS simulation with 3D-printed sinus models. Surgeons' mental workload was assessed with the national aeronautics and space administration-task load index (NASA-TLX). Associations between the total and subscales score of NASA-TLX and surgical skill index, including the board certification status, the number of experienced ESS cases, and the objective structured assessment of technical skills (OSATS), were analyzed. In addition, 10 registrars repeated the simulation surgery, and their NASA-TLX score was compared before and after the repetitive training. Results: The total NASA-TLX score was significantly associated with OSATS score (p = 0.0001). Primary component analysis classified the surgeons' mental burden into three different categories: (1) the skill-level-dependent factors (temporal demand, effort, and performance), (2) the skill-level-independent factors (mental and physical demand), and (3) frustration. After the repetitive training, the skill-level-dependent factors were alleviated (temporal demand; z = -2.3664, p = 0.0091, effort; z = -2.1704, p = 0.0346, and performance; z = -2.5992, p = 0.0017), the independent factors were increased (mental demand; z = -2.5992, p = 0.0023 and physical demand; z = -2.2509, p = 0.0213), and frustration did not change (p = 0.3625). Conclusion: Some of the mental workload during ESS is associated with surgical skill level and alleviated with repetitive training. However, other aspects remain a burden or could worsen even when surgeons have gained surgical experience. Routine assessment of registrars' mental burdens would be necessary during surgical training to sustain their mental health.

Motility Mapping Quantification Using the Classical Optical Flow Algorithm for Small Bowel Crohn's Disease: Comparison with Balloon-assisted Enteroscopy Findings.

PURPOSE: To quantify bowel motility shown on cine MRI using the classical optical flow algorithm and compare it with balloon-assisted enteroscopy (BAE) findings in patients with Crohn's disease (CD). METHODS: This retrospective study included 29 consecutive patients with CD who had undergone MR enterocolonography (MREC) and BAE between March and May 2017. We developed computer software to present motion vector magnitudes between consecutive cine MR images as bowel motility maps via a classical optical flow algorithm using the Horn-Schunck method. Cine MR images were acquired with a balanced steady-state free precession sequence in the coronal direction to capture small bowel motility. The small bowels were divided into three segments. In total, 63 bowel segments were assessed via BAE and MREC. Motility scores on the maps, simplified MR index of activity (sMaRIA), and MREC score derived from a 5-point MR classification were assessed independently by two radiologists and compared with the CD endoscopic index of severity (CDEIS). Correlations were assessed using Spearman's rank coefficient. The areas under the receiver-operating characteristic curve (AUCs) of motility score for differentiating CDEIS was calculated; a P value < 0.05 was considered statistically significant. RESULTS: Motility score was negatively correlated with CDEIS (r = -0.59 [P < 0.001] and -0.54 [P < 0.001]), and the AUCs of motility scores for detecting CDEIS ≥ 3 were 88.2% and 78.6% for observers 1 and 2, respectively. There were no significant differences in the AUC for detecting CDEIS ≥ 3 and CDEIS ≥ 12 between motility and sMaRIA or MREC score. CONCLUSION: The motility map was feasible for locally quantifying the bowel motility. In addition, the motility score on the map reflected the endoscopic inflammatory activity of each small bowel segment in patients with CD; hence, it could be used as a tool in objectively interpreting cine MREC to predict inflammatory activity in CD.

Enhancement of 18F-Fluorodeoxyglucose PET Image Quality by Deep-Learning-Based Image Reconstruction Using Advanced Intelligent Clear-IQ Engine in Semiconductor-Based PET/CT Scanners.

Deep learning (DL) image quality improvement has been studied for application to 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). It is unclear, however, whether DL can increase the quality of images obtained with semiconductor-based PET/CT scanners. This study aimed to compare the quality of semiconductor-based PET/CT scanner images obtained by DL-based technology and conventional OSEM image with Gaussian postfilter. For DL-based data processing implementation, we used Advanced Intelligent Clear-IQ Engine (AiCE, Canon Medical Systems, Tochigi, Japan) and for OSEM images, Gaussian postfilter of 3 mm FWHM is used. Thirty patients who underwent semiconductor-based PET/CT scanner imaging between May 6, 2021, and May 19, 2021, were enrolled. We compared AiCE images and OSEM images and scored them for delineation, image noise, and overall image quality. We also measured standardized uptake values (SUVs) in tumors and healthy tissues and compared them between AiCE and OSEM. AiCE images scored significantly higher than OSEM images for delineation, image noise, and overall image quality. The Fleiss kappa value for the interobserver agreement was 0.57. Among the 21 SUV measurements in healthy organs, 11 (52.4%) measurements were significantly different between AiCE and OSEM images. More pathological lesions were detected in AiCE images as compared with OSEM images, with AiCE images showing higher SUVs for pathological lesions than OSEM images. AiCE can improve the quality of images acquired with semiconductor-based PET/CT scanners, including the noise level, contrast, and tumor detection capability.

Clinical evaluation of a novel molecular diagnosis kit for detecting Helicobacter pylori and clarithromycin-resistant using intragastric fluid.

BACKGROUND: Although there are many Helicobacter pylori (H. pylori) diagnostic methods, the culture and antibiotic susceptibility test is an important method for selecting the most effective H. pylori eradication regimen. However, this diagnostic method is complicated and takes several days; therefore, the development of a rapid and simple diagnostic method is required. Eradication failure due to clarithromycin (CAM) resistance should also be considered. In this study, we report the clinical evaluation of point-of-care testing (POCT) kit using intragastric fluid, a novel kit for detecting H. pylori and CAM resistance. MATERIALS AND METHODS: The study participants were 143 patients suspected of H. pylori infection and had an endoscopic examination. The novel diagnostic kit diagnosed H. pylori infection and CAM resistance-associated mutation using intragastric fluid. To diagnose H. pylori infection, the relationship between the diagnostic kit and conventional diagnostic methods (urea breath test, stool antigen test, culture test, and real-time polymerase chain reaction [PCR]) was evaluated. For CAM resistance-associated mutation detection, the concordance between the diagnostic kit and antibiotic susceptibility test was evaluated. RESULTS: The diagnosis of H. pylori infection with the novel molecular diagnostic kit using intragastric fluid showed significant relationship with conventional diagnostic methods. Especially when the culture was control, the sensitivity was 100% (67/67), the specificity was 95.9% (71/74), and the overall concordance was 97.9% (138/141). The detection of CAM resistance-associated mutations had a concordance rate of 97.0% (65/67) when compared with the antibiotic susceptibility test. CONCLUSIONS: The H. pylori molecular POCT kit uses intragastric fluid as a sample and can diagnose H. pylori infection and detect CAM resistance-associated mutations within an hour. This novel kit is expected to prove useful in selecting the most effective eradication regimen for H. pylori.

Aberrant autophagy in lysosomal storage disorders marked by a lysosomal SNARE protein shortage due to suppression of endocytosis.

Lysosomal storage disorders (LSDs) are inherited metabolic diseases caused by genetic defects in lysosomal enzymes or related factors. LSDs are associated with excessive accumulation of natural substrates in lysosomes leading to central nervous system and peripheral tissue damage. Abnormal autophagy is also involved in pathogenesis, although the underlying mechanisms remain unclear. We demonstrated that impairment of lysosome-autophagosome fusion is due to suppressed endocytosis in LSDs. The fusion was reduced in several LSD cells and the brains of LSD model mice, suggesting that the completion of autophagy is suppressed by the accumulation of substrates. In this brain, the expression of the soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) proteins, VAMP8 and Syntaxin7, was decreased on the lysosomal surface but not intracellular. This aberrant autophagy preceded the development of pathological phenotypes in LSD-model mice. Furthermore, the enzyme deficiency leading to the substrate accumulation could suppress endocytosis, and the inhibited endocytosis decreased SNARE proteins localized on lysosomes. These findings suggest that the shortage of SNARE proteins on lysosomes is one of the reasons for the impairment of lysosome-autophagosome fusion in LSD cells. Defects in lysosomal enzyme activity suppress endocytosis and decrease the supply of intracellular SNARE proteins recruited to lysosomes. This shortage of lysosomal SNARE proteins impairs lysosome-autophagosome fusion in lysosomal storage disorders.

Repetitive simulation training with novel 3D-printed sinus models for functional endoscopic sinus surgeries.

Background: The purpose of this study was to find a utility of a newly developed 3D-printed sinus model and to evaluate the educational benefit of simulation training with the models for functional endoscopic sinus surgery (FESS). Material and methods: Forty-seven otolaryngologists were categorized as experts (board-certified physicians with ≥200 experiences of FESS, n = 9), intermediates (board-certified physicians with <200 experiences of FESS, n = 19), and novices (registrars, n = 19). They performed FESS simulation training on 3D-printed models manufactured from DICOM images of computed tomography (CT) scan of real patients. Their surgical performance was assessed with the objective structured assessment of technical skills (OSATS) score and dissection quality evaluated radiologically with a postdissection CT scan. First we evaluated the face, content, and constructive values. Second we evaluated the educational benefit of the training. Ten novices underwent training (training group) and their outcomes were compared to the remaining novices without training (control group). The training group performed cadaveric FESS surgeries before and after the repetitive training. Results: The feedback from experts revealed high face and content value of the 3D-printed models. Experts, intermediates, and novices demonstrated statistical differences in their OSATS scores (74.7 ± 3.6, 58.3 ± 10.1, and 43.1 ± 11.1, respectively, p < .001), and dissection quality (81.1 ± 13.1, 93.7 ± 15.1, and 126.4 ± 25.2, respectively, p < .001). The training group improved their OSATS score (41.1 ± 8.0 to 61.1 ± 6.9, p < .001) and dissection quality (122.1 ± 22.2 to 90.9 ± 10.3, p = .013), while the control group not. After training, 80% of novices with no prior FESS experiences completed surgeries on cadaver sinuses. Conclusion: Repeated training using the models revealed an initial learning curve in novices, which was confirmed in cadaveric mock FESS surgeries. Level of evidence: N/A.

Primary Duodenal Adenocarcinoma Expressing Carbonic Anhydrase IX.

Primary duodenal adenocarcinoma is a rare malignancy whose carbonic anhydrase IX (CA9) expression remains poorly understood. A 73-year-old man visited our hospital for a medical checkup. Transnasal endoscopy revealed a submucosal, tumor-like lesion with a central depression located in the descending part of the duodenum on white light imaging. On texture and color enhancement imaging mode 1, the lesion was highlighted as a reddish, elevated lesion with an irregular mucosa in its central depressed area. Pancreaticoduodenectomy was performed on the suspicion of duodenal adenocarcinoma for biopsy and endoscopic diagnosis, which led to the lesion being diagnosed as tubular adenocarcinoma, pT1b (SM). Immunohistological staining revealed an adenocarcinomatous component positive for CA9, as well as a normal duodenal mucosa. To our knowledge, this report is among the first to describe CA9-expressing primary duodenal adenocarcinoma.

Potential generation of nano-sized mist by passing a solution through dielectric barrier discharge.

Plasma medicine, a therapeutic technology that uses atmospheric-pressure plasma, is attracting much attention as an innovative tool for the medical field. Most of the plasma biomedical tools use direct effects, such as heat, optical stimulation, and reactive chemical species, on the lesion. Nanoparticulation techniques using indirect action by plasma, i.e., generation of electric fields, have the potential to be applied to promote transdermal absorption, where drugs pass through the barrier function of skin and penetrate into internal tissues. Here, we show a method to directly generate the nano-sized mist by passing a solution through the dielectric barrier discharge. This method enables us to produce the mist potentially in the nanometer size range for both water-based and oil-based solutions. Ease of mist generation was influenced by the plasma-induced changes in physical and chemical characteristics, including electrical conductivity, viscosity, and chemical species. We anticipate the developed method for nano-sized mist generation to provide a technique in the applications of the transdermal absorption system, including those related to pharmaceuticals and cosmetics.

Fitz-Hugh-Curtis Syndrome Presenting as Perihepatic and Subcapsular Enhancement on MRI.

Fitz-Hugh-Curtis syndrome (FHCS) is a rare complication of pelvic inflammatory disease and its MRI findings remain poorly described. A 34-year-old woman was raced to our hospital with slight fever and severe right upper quadrant pain. Gadoxetic acid-enhanced magnetic resonance imaging revealed high-intensity regions in the surface and subcapsule of the right liver on T2-weighted imaging and on diffusion-weighted imaging. A definitive diagnosis of FHCS was confirmed based on high titers of serum IgA and IgG antibodies to Chlamydia trachomatis. She was treated with oral azithromycin and discharged 6 days after admission with improvement of her symptoms. To our knowledge, this report represents a valuable addition to the FHCS literature describing MRI findings in the early stage of FHCS onset.

Fast calculation method based on hidden region continuity for computer-generated holograms with multiple cameras in a sports scene.

We propose, to the best of our knowledge, the world's first system capable of fast calculating computer-generated holograms (CGHs) from a large-scale outdoor sports scene captured with multiple RGB cameras. In the system, we introduce a fast calculation method focusing on hidden region continuity (HRC) that frequently appears in a point cloud of a 3D sports scene generated from free-viewpoint video technology. The experimental results show that the calculation time of the proposed HRC method is five to 10 times faster than that of the point-based method, which is one of the common CGH calculation methods.

Vonoprazan-Associated Gastric Mucosal Redness in Non-Helicobacter pylori-Infected and Helicobacter pylori-Eradicated Stomach.

Vonoprazan-associated gastric mucosal redness is rare, and its endoscopic and pathological features remain poorly described. We report 4 cases of vonoprazan-associated gastric mucosal redness, that is, 2 cases each in non-Helicobacter pylori-infected and -eradicated stomach. In all cases, esophagogastroduodenoscopy demonstrated spotty and linear redness newly appearing in the greater curvature of the gastric body after initiation of vonoprazan but disappearing after its discontinuation. A tissue biopsy taken from the gastric mucosa with redness revealed various pathological findings and included inflammatory cell infiltration, parietal cell protrusions, oxyntic gland dilatations, congestion, focal hemorrhage with congestion beneath the basement membrane, and vacuolar degeneration of parietal cells. To our knowledge, this is the second report describing the endoscopic and pathological features of vonoprazan-associated gastric mucosal redness.

Oxaliplatin-Associated Amaurosis Fugax.

Oxaliplatin-associated amaurosis fugax has not been reported, and its clinical course and treatment remain largely unclear. A 70-year-old man with advanced gastric cancer was treated with the SOX regimen. After cycle 1 of oxaliplatin infusion, the patient realized that his right eye had visual field impairment, which he described as darkening of the right half of his visual field and loss of vision lasting about 1 min and occurring about 7 times a day. The daily frequency of this occurrence gradually decreased, and his visual field impairment improved in 1 week. However, as the same symptoms recurred from cycle 2 to cycle 5 of treatment, oxaliplatin was discontinued from cycle 6 and switched to S-1 monotherapy. Subsequently, the patient's amaurosis fugax improved. To our knowledge, this is the first report describing clinical course and treatment of oxaliplatin-associated amaurosis fugax.

CT Abnormalities of the Pancreas Associated With the Subsequent Diagnosis of Clinical Stage I Pancreatic Ductal Adenocarcinoma More Than 1 Year Later: A Case-Control Study.

BACKGROUND. Pancreatic ductal adenocarcinoma (PDAC) is highly lethal, partly because of challenges in early diagnosis. However, the prognosis for earlier stages (carcinoma in situ or category T1a invasive carcinoma) is relatively favorable. OBJECTIVE. The purpose of this study was to investigate findings of an earlier diagnosis of PDAC on CT examinations performed at least 1 year before the diagnosis of clinical stage I PDAC. METHODS. This retrospective study included 103 patients with clinical stage I PDAC and a CT examination performed at least 1 year before the CT examination that detected PDAC, as well as 103 control patients without PDAC on CT examinations separated by at least 10 years. The frequency and temporal characteristics of focal pancreatic abnormalities (pancreatic mass, main pancreatic duct [MPD] change, parenchymal atrophy, faint parenchymal enhancement, cyst, and parenchymal calcification) seen on CT examinations conducted before diagnosis (prediagnostic CT) were determined. RESULTS. A focal pancreatic abnormality was present on the most recent prediagnostic CT examination in 55/103 (53.4%) patients with PDAC versus 21/103 (20.4%) control patients (p < .001). In patients with PDAC, the most common focal abnormalities on prediagnostic CT were atrophy (39/103, 37.9%), faint enhancement (17/65, 26.2%), and MPD change (14/103, 13.6%), which were all more frequent in patients with PDAC than in control patients (p < .05). In 54/55 (98.2%) patients with PDAC, the PDAC corresponded to the site of a focal abnormality (exact location or the abnormality's upstream or downstream edge) on prediagnostic CT. Frequency of focal abnormalities decreased with increasing time before CT that detected PDAC (> 1 to ≤ 2 years before diagnosis, 64.9%; > 2 to ≤ 3 years, 49.2%; > 3 to ≤ 5 years, 41.8%; > 5 to ≤ 7 years, 29.7%; > 7 to ≤ 10 years, 18.5%; more than 10 years, 0%). Mean duration from the finding's initial appearance to diagnosis of PDAC was 4.6 years for atrophy, 3.3 years for faint enhancement, and 1.1 years for MPD change. CONCLUSION. Most patients with clinical stage I PDAC showed focal pancreatic abnormalities on CT performed at least 1 year before diagnosis. Focal MPD change exhibited the shortest duration from its development to subsequent diagnosis, whereas atrophy and faint enhancement exhibited a relatively prolonged course. CLINICAL IMPACT. These findings could facilitate earlier PDAC diagnosis and thus improve prognosis.

First isolation of Trichophyton bullosum from a horse with dermatophytosis in Japan.

Trichophyton bullosum is a zoophilic dermatophyte that has been rarely isolated from horses and humans in Africa and Europe. This is the first reported isolation of T. bullosum from a horse with dermatophytosis in Japan. The isolate from a skin lesion formed a cream-colored and waxy colony that was slightly elevated in the center. Sequencing of the internal transcribe spacer region of the isolate revealed that it was 100% identical to that of T. bullosum.

Evaluation of the basic assay performance of the GeneSoc® rapid PCR testing system for detection of severe acute respiratory syndrome coronavirus 2.

In the ongoing coronavirus disease 2019 (COVID-19) pandemic, PCR has been widely used for screening patients displaying relevant symptoms. The rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enables prompt diagnosis and the implementation of proper precautionary and isolation measures for the patient. In the present study, we aimed to evaluate the basic assay performance of an innovative PCR system, GeneSoC® (Kyorin Pharmaceutical Co. Ltd., Tokyo, Japan). A total of 1,445 clinical samples were submitted to the clinical laboratory, including confirmed or suspected cases of COVID-19, from February 13 to August 31. Specimen types included nasopharyngeal swabs. The sampling was performed several times for each patient every 2-7 days. Using this system, sequences specific for SARS-CoV-2 RNA could be detected in a sample within 10-15 min using the microfluidic thermal cycling technology. Analytical sensitivity studies showed that GeneSoC® could detect the target sequence of the viral envelope and RNA-dependent RNA-polymerase (RdRp) genes at 5 and 10 copies/µL, respectively. The precision of the GeneSoC® measurements using clinical isolates of the virus at a concentration of 103 copies/µL was favorable for both the genes; within-run repeatability and between-run reproducibility coefficient of variation values were less than 3% and 2%, respectively; and the reproducibility of inter-detection units was less than 5%. Method comparison by LightCycler® 480 showed the positive and negative agreement to be 100% [(174/174) and (1271/1271), respectively]. GeneSoC® proved to be a rapid and reliable detection system for the prompt diagnosis of symptomatic COVID-19 patients and could help reduce the spread of infections and facilitate more rapid treatment of infected patients.

Deep learning-based image quality improvement of 18F-fluorodeoxyglucose positron emission tomography: a retrospective observational study.

BACKGROUND: Deep learning (DL)-based image quality improvement is a novel technique based on convolutional neural networks. The aim of this study was to compare the clinical value of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) images obtained with the DL method with those obtained using a Gaussian filter. METHODS: Fifty patients with a mean age of 64.4 (range, 19-88) years who underwent 18F-FDG PET/CT between April 2019 and May 2019 were included in the study. PET images were obtained with the DL method in addition to conventional images reconstructed with three-dimensional time of flight-ordered subset expectation maximization and filtered with a Gaussian filter as a baseline for comparison. The reconstructed images were reviewed by two nuclear medicine physicians and scored from 1 (poor) to 5 (excellent) for tumor delineation, overall image quality, and image noise. For the semi-quantitative analysis, standardized uptake values in tumors and healthy tissues were compared between images obtained using the DL method and those obtained with a Gaussian filter. RESULTS: Images acquired using the DL method scored significantly higher for tumor delineation, overall image quality, and image noise compared to baseline (P < 0.001). The Fleiss' kappa value for overall inter-reader agreement was 0.78. The standardized uptake values in tumor obtained by DL were significantly higher than those acquired using a Gaussian filter (P < 0.001). CONCLUSIONS: Deep learning method improves the quality of PET images.

Viral Interference as a Factor of False-Negative in the Infectious Adenovirus Detection Using Integrated Cell Culture-PCR with a BGM Cell Line.

This study investigated the influence of viral interference on the detection of enteric viruses using the integrated cell culture (ICC)-PCR with a BGM cell line. It was possible to detect 102 plaque-forming units (PFU)/flask of enterovirus 71 (EV71) in spite of the presence of 104 PFU/flask of adenovirus 40 (AdV40). Meanwhile, 104 PFU/flask of AdV40 was not detected in the presence of 102 PFU/flask of EV71. This inhibition of AdV40 detection using ICC-PCR was attributable to the growth of EV71, because the addition of a growth inhibitor of EV71 (rupintrivir) neutralized the detection inhibition of AdV40. The growth inhibition of AdV40 under co-infection with EV71 is probably caused by the immune responses of EV71-infected cells. AdV is frequently used as a fecal contamination indicator of environmental water, but this study demonstrated that false-negative detection of infectious AdV using ICC-PCR could be caused by the co-existence of infectious EV in a water sample. The addition of rupintrivir could prevent false-negative detection of AdV using ICC-PCR. This study, therefore, emphasizes the importance of confirming the presence of multiple enteric viruses in a sample derived from environmental water prior to the application of ICC-PCR because the viral interference phenomenon may lead to the false-negative detection of target viruses.