Development of a novel fluorogenic assay method for screening inhibitors of bovine leukemia virus protease and identification of mitorubrinic acid as an anti-BLV compound.

Bovine leukemia virus (BLV) causes enzootic bovine leukosis, a fatal cattle disease that leads to significant economic losses in the livestock industry. Currently, no effective BLV countermeasures exist, except testing and culling. In this study, we developed a high-throughput fluorogenic assay to evaluate the inhibitory activity of various compounds on BLV protease, an essential enzyme for viral replication. The developed assay method was used to screen a chemical library, and mitorubrinic acid was identified as a BLV protease inhibitor that exhibited stronger inhibitory activity than amprenavir. Additionally, the anti-BLV activity of both compounds was evaluated using a cell-based assay, and mitorubrinic acid was found to exhibit inhibitory activity without cytotoxicity. This study presents the first report of a natural inhibitor of BLV protease-mitorubrinic acid-a potential candidate for the development of anti-BLV drugs. The developed method can be used for high-throughput screening of large-scale chemical libraries.

Delayed rupture of the iliac artery after endovascular therapy.

Iliac artery rupture during endovascular therapy (EVT) is a life-threatening complication requiring prompt diagnosis and treatment. However, delayed rupture of the iliac artery after EVT is rare, and its predictive value remains unknown. Herein, we present the case of a 75-year-old woman who developed delayed iliac artery rupture 12 h after balloon angioplasty and placement of a self-expandable stent in the left iliac artery. Hemostasis was achieved with a covered stent graft. However, the patient died of hemorrhagic shock. From the review of previous case reports and the pathological findings of the current case, increased radial force due to overlapping stent and kinking of the iliac artery may be associated with delayed iliac artery rupture. Learning objective: Delayed iliac artery rupture after endovascular therapy is rare but with a poor prognosis. Hemostasis can be achieved using a covered stent; however, the outcome could be fatal. Based on pathological findings and previous case reports, increased radial force at the stent site and kinking of the iliac artery may be associated with delayed iliac artery rupture. Self-expandable stent probably should not be overlapped at the site where kinking is likely to occur, even if long stenting is needed.

Characterization of extended-spectrum ß-lactamase-producing Escherichia coli isolated from municipal and hospital wastewater in Japan.

OBJECTIVES: The purpose of this study was to characterize the strains of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) isolated from municipal and hospital wastewater by detecting antibiotic resistance genes (ARGs) as well as antibiotic susceptibility. To identify the source of ESBL-EC, multi-locus sequence typing and typing plasmids that may carry ESBL-producing genes were conducted. METHODS: Wastewater was sampled twice a month from February 2019 to February 2020 from a municipal wastewater treatment plant and hospital located in a city in northeastern Japan. Throughout the study period, 279 and 37 strains of ESBL-EC were isolated from municipal and hospital wastewater, respectively. RESULTS: All 316 isolates were resistant to ampicillin and cefotaxime and susceptible to imipenem and tigecycline. Almost all (98.1%) of the ESBL-EC isolates possessed blaCTX-M, and the blaCTX-M-9 group was detected most frequently (62.3%). Multi-locus sequence typing revealed a higher diversity of sequence types (STs) in the isolates from municipal wastewater than in those from hospital wastewater; although ST131, which recently caused nosocomial- and community-associated infections worldwide, was dominant in both types of wastewater. All ST131 isolates possessed the IncFII plasmid, which is often reported to carry blaCTX-M. CONCLUSIONS: These results demonstrated that healthy people carry clinically important antibiotic-resistant bacteria and ARGs, motivating routine monitoring of municipal wastewater to detect such antibiotic-resistant bacteria and ARGs from a variety of sources supported by the high diversity of STs in the present study.

Design and synthesis of versatile GSTP1-specific fluorogenic substrates for the highly sensitive detection of GSTP1 activity in living cells.

Pi-class glutathione S-transferase (GSTP1) is a detoxification enzyme that is highly expressed in various types of cancer cells and is a promising target for cancer imaging and therapy. Ps-TAc, an acetylated derivative of the GSTP1-specific fluorogenic substrate Ps-TG, is attracting attention as an effective GSTP1 fluorescent probe, and has been successfully used to visualize intracellular GSTP1 activity. Ps-TAc is a prodrug type fluorescent probe in which the phenolic hydroxyl group of Ps-TG is acetylated and thus is susceptible to nonspecific hydrolysis, potentially compromising its ability to detect GSTP1 activity. Here, we describe the development of a highly selective fluorogenic GSTP1 substrate that is membrane permeable and does not involve esterification and show its application to live-cell imaging and FACS analysis. We designed and synthesized several compounds with benzylsulfone substituents instead of the mesyl group of Ps-TG and tested their fluorescence activation by GSTP1 catalysis in vitro and in cellulo. Of the test compounds, Ps-TG3 was the most suitable for the visualization of intracellular GSTP1 activity because the signal from living cells increased significantly when MK-571, an inhibitor of multidrug resistance proteins (MRPs), was simultaneously loaded. The results obtained by co-loading Ps-TG3 and MK571 into GSTP1-nonexpressing cells suggest that Ps-TG3 can be a substrate for MRPs. The usefulness of Ps-TG3 was demonstrated by fluorescence imaging of several cancer cell cultures and FACS analysis of lymphoma cells. The results presented here suggest that Ps-TG3, in combination with MK571, is useful for visualizing and detecting intracellular GSTP1 activity in cancer cells that highly express GSTP1.

Pi-Class Glutathione S-transferase (GSTP1)-Selective Fluorescent Probes for Multicolour Imaging with Various Cancer-Associated Enzymes.

Pi-class glutathione S-transferase (GSTP1) is highly expressed in a wide variety of human cancer tissues compared to the corresponding normal counterpart. Therefore, GSTP1 is a potential target enzyme for overcoming resistance to chemotherapeutic agents or visualizing specific lesions such as cancer. Here, we present orange and red fluorescence-emitting probes selective for GSTP1. Carbofluorescein and TokyoMagenta fluorophores were modified with a previously described GSTP1-selective chromogenic compound to generate orange and red fluorescence probes, respectively. Of these probes, Ps-CF, the orange fluorescence-emitting probe, was confirmed to be highly specific for detecting GSTP1 exogenously or endogenously expressed in various cancer cells. Additionally, it was demonstrated that Ps-CF is applicable for the simultaneous detection of GSTP1 and another cancer-associated enzyme by using a green fluorescence emitting γ-glutamyl transpeptidase (GGT) probe. In conclusion, the fluorescent probes developed in this study enable the simultaneous detection of multiple tumour markers such as GSTP1 with other cancer-associated enzymes by concurrently using spectrally distinguished fluorescent probes, potentially broadening the scope of cancer detection.

Prediction of Microcystis Occurrences and Analysis Using Machine Learning in High-Dimension, Low-Sample-Size and Imbalanced Water Quality Data.

Machine learning, Deep learning, and water quality data have been used in recent years to predict the outbreak of harmful algae, especially Microcystis, and analyze outbreak causes. However, for various reasons, water quality data are often High-Dimension, Low-Sample- Size (HDLSS), meaning the sample size is lower than the number of dimensions. Moreover, imbalance problems may arise due to bias in the occurrence frequency of Microcystis. These problems make predicting the occurrence of Microcystis and analyzing its causes with machine learning difficult. In this study, a machine learning model that applies Feature Engineering (FE) and Feature Selection (FS) algorithms are used to predict outbreaks of Microcystis and analyze the outbreak factors from imbalanced HDLSS water quality data. The prediction performance was verified with binary classification to determine whether Microcystis would occur in the future by applying three machine learning models to four data patterns. The cause analysis of Microcystis occurrence was performed by visualizing the results of applying FE and FS. For the test data, the predictive performance of FE and FS methods was significantly better than that of the conventional method, with an accuracy of .108 points and an F-value of .691 points higher than the conventional method. A prediction performance increase was observed with a smaller model capacity. Data-driven analysis suggested that total nitrogen, chemical oxygen demand, chlorophyll-a, dissolved oxygen saturation, and water temperature are associated with Microcystis occurrences. The results also indicated that basic statistics of the water quality distribution (especially mean, standard deviation, and skewness) over a year, not the concentrations of water components, are related to the occurrence of Microcystis. These are new findings not found in previous studies and are expected to contribute significantly to future studies of algae. This study provides a method for analyzing water quality data with high-dimensionality and small samples, imbalance problems, or both.

Orbital Intravascular Natural Killer/T-cell Lymphoma: An Unusual Cause of Ocular Symptoms.

Orbital intravascular lymphoma is rare and typically of B-cell lineage. In this study, we report a patient who developed orbital lesions of intravascular natural killer/T-cell lymphoma (IVNKL), an extremely rare lymphoma. An 88-year-old man presented with rapidly progressive right vision loss and double vision. A neurological examination revealed that he had decreased visual acuity and severe oculomotor impairment in the right eye. Magnetic resonance imaging showed right-dominant, nonmass lesions in both orbits. No lesions were found in the lymph nodes, skin, or brain. The patient received immunosuppressive and antifungal therapy, but his clinical condition rapidly deteriorated, and he died of multiple organ failure. Autopsy revealed natural killer/T-cell lymphoma proliferation within the lumina of small blood vessels in multiple organs, including the ocular adnexa of the right orbit. These findings show that he was ultimately diagnosed with IVNKL. IVNKL could initially cause ocular symptoms due to the involvement of the ocular adnexa. Ocular involvements have not been described previously. Even if patients initially present with only ocular symptoms, IVNKL should be considered.

Use of a Deep Learning Approach for the Sensitive Prediction of Hepatitis B Surface Antigen Levels in Inactive Carrier Patients.

Deep learning is a subset of machine learning that can be employed to accurately predict biological transitions. Eliminating hepatitis B surface antigens (HBsAgs) is the final therapeutic endpoint for chronic hepatitis B. Reliable predictors of the disappearance or reduction in HBsAg levels have not been established. Accurate predictions are vital to successful treatment, and corresponding efforts are ongoing worldwide. Therefore, this study aimed to identify an optimal deep learning model to predict the changes in HBsAg levels in daily clinical practice for inactive carrier patients. We identified patients whose HBsAg levels were evaluated over 10 years. The results of routine liver biochemical function tests, including serum HBsAg levels for 1, 2, 5, and 10 years, and biometric information were obtained. Data of 90 patients were included for adaptive training. The predictive models were built based on algorithms set up by SONY Neural Network Console, and their accuracy was compared using statistical analysis. Multiple regression analysis revealed a mean absolute percentage error of 58%, and deep learning revealed a mean absolute percentage error of 15%; thus, deep learning is an accurate predictive discriminant tool. This study demonstrated the potential of deep learning algorithms to predict clinical outcomes.

Autopsy findings of left atrial appendage closure device.

We report an autopsy case of an 80-year-old woman who underwent left atrial appendage closure with a WATCHMAN (Boston Scientific, St. Paul, MN, USA) device. This is the first report of histologic assessment following left atrial appendage closure with a WATCHMAN device at 3 months. Gross and histopathological examinations revealed neoendocardial coverage of the WATCHMAN device. Partial endothelialization was verified by CD34 staining; however, it remains unclear when complete endothelialization is likely to occur.

Hepatitis C virus relapse after successful treatment with direct-acting antivirals, followed by sarcomatous changes in hepatocellular carcinoma: a case report.

BACKGROUND: Combination therapy of interferon and ribavirin has traditionally been used to eradicate hepatitis C virus. The sustained virologic response achieved with interferon-related therapy is persistent, and late relapses after achieving sustained virologic response at 24 weeks using this therapy are reportedly rare (< 1%). In 2014, interferon-free therapy with direct-acting antivirals was developed, and the rate of sustained virologic response was improved. However, the persistence thereof remains uncertain, and the appropriate follow-up period for hepatitis C virus-positive patients is under discussion. CASE PRESENTATION: A 74-year-old Japanese man who had hepatitis C virus-related hepatocellular carcinoma and was successfully treated with radiofrequency ablation four times underwent direct-acting antiviral therapy with daclatasvir and asunaprevir; sustained virologic response at 24 weeks was confirmed. However, although he had no high risk factors for reinfection, hepatitis C virus ribonucleic acid was detected again 6 months after achieving sustained virologic response at 24 weeks. Moreover, he developed active hepatitis with an increased viral load. Five months after development of hepatitis, recurrent hepatocellular carcinoma emerged in segment II, where we had performed radiofrequency ablation 17 months previously. The recurrent hepatocellular carcinoma enlarged quite rapidly and induced multiple peritoneal disseminations and lung metastases. He died 3 months after the abrupt recurrence. A sarcomatous change in the hepatocellular carcinoma was identified during the autopsy. CONCLUSIONS: Although sustained virologic response at 24 weeks has generally been regarded to denote complete eradication of hepatitis C virus, we present a patient in whom hepatitis C virus recurred 6 months after achieving sustained virologic response at 24 weeks with direct-acting antiviral therapy. In addition, a sarcomatous change in hepatocellular carcinoma emerged 5 months after active hepatitis developed due to late hepatitis C virus relapse in this case. The sarcomatous change in hepatocellular carcinoma is generally thought to be related to anticancer therapies, such as radiofrequency ablation. However, in this case, late viral relapse and active hepatitis in addition to the previous radiofrequency ablation could have been the trigger. There may be a need for follow-up of hepatitis C virus ribonucleic acid beyond sustained virologic response at 24 weeks with direct-acting antiviral therapy, owing to the possibility of late viral relapse and tumorigenesis.

4-Bromo-1,8-naphthalimide derivatives as fluorogenic substrates for live cell imaging of glutathione S-transferase (GST) activity.

Fluorogenic substrates are used to visualize the activity of cancer-associated enzymes and to interpret biological events. Certain types of glutathione S-transferase (GST), such as Pi class GST (referred to as GSTP1), are more highly expressed in a wide variety of human cancer tissues compared to their corresponding normal tissues. Pi class GST is thus a cancer cell molecular marker and potential target for overcoming resistance to chemotherapy. Here, we report that 4-bromo-1,8-naphthalimide (BrNaph) is a practical fluorogenic GST substrate. We have found that HE-BrNaph, an N-hydroxyethyl derivative, shows remarkable fluorescence enhancement upon GST-catalyzed SNAr replacement of the bromo group with a glutathionyl group. This substitution was highly selective and occurred only in the presence of GSH/GSTs; no non-enzymatic reaction was observed. We demonstrated that HE-BrNaph allows visualization of GST activity in living cells and enables to distinguish cancer cells from normal cells. Further, various N-substitutions in BrNaph retain susceptibility to enzymatic activity and isozyme selectivity, suggesting the applicability of BrNaph derivatives. Thus, BrNaph and its derivatives are GST substrates useful for fluorescence imaging and the intracellular detection of GSTP1 activity in living cells.

A highly selective fluorogenic substrate for imaging glutathione S-transferase P1: development and cellular applicability in epigenetic studies.

Pi-class glutathione S-transferase (GSTP1) is a molecular marker enzyme whose expression level is altered in various malignant tumour tissues. Herein, we report the first highly selective fluorogenic GSTP1 substrate, Ps-TG, and its membrane-permeable derivative Ps-TAc, for specific visualization of intracellular GSTP1 activity in cancer cells or epigenetically regulated GSTP1 expression.

A case of adenomyoepithelioma with myoepithelial carcinoma of the breast.

Adenomyoepithelioma with myoepithelial carcinoma of the breast is rare and diagnosed with histology and immunohistochemistry. We present a case of malignant transformation over 10 years, with ultrasonographic findings, highlighting the importance of an early excisional biopsy. Conservative surgery and radiation therapy were performed. There was no recurrence for 2 years.

The hepatic capsular arteries: imaging features and clinical significance.

BACKGROUND: Although the anatomical features of the hepatic capsular arteries have been previously reported, the radiological and clinical importance of these arteries has not been well documented. IMAGING FINDINGS: We injected barium sulfate into the intra- and extra-hepatic arteries in cadavers to investigate the hepatic capsular arteries. The web-like hepatic capsular arteries derived from the capsular branch of the peripheral hepatic arteries are called isolated arteries. There were anastomoses between the intra- and extra-hepatic arteries (inferior phrenic artery, superior falciform ligament artery, and cystic artery) through the hepatic capsular arteries. CLINICAL SIGNIFICANCE: We reviewed the radiology database and assessed clinical cases. When the hepatic artery is occluded, the collateral vessels, such as the inferior phrenic artery and the superior falciform ligament artery, develop via the hepatic capsular arteries at the right triangular ligament and falciform ligament, respectively. Bleeding from capsular arteries causes extensions of the subcapsular hematoma. CONCLUSION: The hepatic capsular arteries spread along the hepatic surface and constitute the vascular network throughout the liver. These arteries play an important role in collateral circulation in various clinical situations, as well as subcapsular hematoma.

Nivolumab-induced myocardial necrosis in a patient with lung cancer: A case report.

A 74-year-old man with lung adenocarcinoma recurrence was admitted to our hospital because of dyspnea 7 days after receiving initial immunotherapy with nivolumab. Electrocardiography revealed ST-segment elevation in V1-6 and echocardiography showed a markedly reduced left ventricular ejection fraction of 9% and akinesis of the anteroseptal wall and apex. He died from acute heart failure 3 days after admission. Microscopically, multiple small foci of myocardial necrosis with few inflammatory cells were scattered in both ventricles. Obstruction of the coronary artery was not identified. We believed that the cause of death was acute heart failure possibly due to nivolumab-induced myocardial necrosis.

Rapidly progressive miliary brain metastasis of lung cancer after EGFR tyrosine kinase inhibitor discontinuation: An autopsy report.

Miliary brain metastasis is a rare type of brain metastasis, in which carcinoma cells disseminate to numerous foci confined to Virchow-Robin/subpial spaces. Symptoms usually progress within several months, and magnetic resonance imaging (MRI) shows multiple small contrast-enhancing lesions. We report an autopsy case of a patient who rapidly deteriorated within a week due to miliary brain metastasis after epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) discontinuation, without contrast-enhancing lesions on MRI. A 74-year-old woman was diagnosed with stage IV lung adenocarcinoma with EGFR L868R mutation 2 years before presentation. Gefitinib, an EGFR-TKI was started. After 7 months, multiple new punctate contrast-enhancing lesions in the cerebral cortex appeared. After switching to another EGFR-TKI, erlotinib, these lesions disappeared. One year later, erlotinib was discontinued because of disease progression in the lung and docetaxel was initiated. Sixteen days later, cognitive decline appeared which rapidly progressed to bedridden state in 4 days. MRI showed multiple cortical small fluid-attenuated inversion recovery high intensity lesions which lacked contrast enhancement. The patient exhibited a state of akinetic mutism within a few days, and died 52 days after the appearance of neurological symptoms. The rapid progression indicated disease flare after EGFR-TKI discontinuation. Autopsy revealed numerous foci of metastasis in the cerebral cortex, basal ganglia, thalamus, and cerebellum, in which cancer cells were mostly confined to the Virchow-Robin/subpial spaces. These pathological findings were compatible with previous reports of miliary brain metastasis. Recent reports suggest that early disseminated cancer cells can survive for a long time and even remain after chemotherapy in supportive niches, and Virchow-Robin spaces are the niches in the brain. Our case suggests that these cancer cells may rapidly proliferate as a withdrawal burst after discontinuation of molecular targeted drugs, and show pathological findings of miliary brain metastasis.

Acute Bilateral Oculomotor Nerve Palsy in an Adult Patient with Neisseria meningitidis.

A 69-year-old woman was admitted to our hospital with a fever, dizziness, and headache caused by Neisseria meningitidis. After ceftriaxone was administered, she suddenly developed bilateral oculomotor nerve palsy. Intra-orbital magnetic resonance imaging using appropriate sequences revealed that her bilateral third intracranial nerves were enlarged and enhanced. She achieved complete recovery by two months after additional short-term treatment with intravenous immunoglobulin and methylprednisolone. Although intracranial nerve disorders that result from bacterial meningitis are most frequently reported in children, it is noteworthy that it can also cause focal intracranial nerve inflammation with ophthalmoparesis in N. meningitidis infection in adults.

Granulomatosis with Polyangiitis Localized in the Greater Omentum.

Granulomatosis with polyangiitis (GPA) is known as anti-neutrophil cytoplasmic antibody- (ANCA-) associated small vessel vasculitis and typically manifests as pulmonary-renal syndrome, but the disease is not limited to pulmonary or renal systems. The inflammation can involve whole body organs. In addition, the ANCA titer does not always become positive. Here, we describe the case of a 91-year-old man who presented with umbilical pain and fever of unknown origin. Only the increased computed tomography value of the greater omentum suggested intra-abdominal inflammation; however, serological examinations, including the ANCA level, could not reveal the focus or cause of symptoms. Finally, the histopathological examination of specimens surgically excised from the greater omentum demonstrated GPA limited to the greater omentum. This report reminds physicians to consider GPA in the differential diagnosis of acute abdominal pain or fever of unknown origin.

Pulmonary Tumor Thrombotic Microangiopathy due to Advanced Gastric Cancer with Virchow's Node Metastasis.

Pulmonary tumor thrombotic microangiopathy (PTTM) is a fatal cancer-related complication characterized by severe progressive pulmonary hypertension. Antemortem diagnosis is difficult owing to the rapid progression of the condition, especially when the patient has no known malignancies and initially presents with pulmonary hypertension. Here we report a case of PTTM due to occult gastric cancer with metastasis in the left supraclavicular lymph node, also known as Virchow's node. Enlarged Virchow's node is an important indicator of advanced gastric cancer. In patients with progressive pulmonary hypertension of unknown origin, enlarged Virchow's node can be an important indicator for the diagnosis of PTTM.

Pancreaticoduodenectomy for an Ampullary Region Carcinoma Occurred in Annular Pancreas Coexistent with Replaced Common Hepatic Artery.

INTRODUCTION: Annular pancreas is a rare congenital abnormality characterized by a ring of pancreatic tissue surrounding the descending portion of the duodenum. Annular pancreas coexisting with replaced common hepatic artery which is also a rare anatomical variation has not been reported previously. CASE PRESENTATION: A 53-year-old man visited our hospital complaining of epigastric pain. Based on radiological examinations, he was diagnosed as having pancreatitis, annular pancreas, and hepatomesenteric trunk. One month later, obstructive jaundice developed. Endoscopic examination revealed ampullary region carcinoma. We performed pancreaticoduodenectomy using the "artery-first" approach. DISCUSSION: Both annular pancreas and common hepatic artery anomaly are rare. High-quality preoperative imaging and awareness of such rare conditions are necessary for operative safety. Although the embryological relationship between these anomalies is uncertain, the present case may suggest some relevance between the two. CONCLUSION: The "artery-first" approach may be a useful method for pancreaticoduodenectomy in patients who have an anatomical abnormality.