Heterologous production of a new lanthipeptide boletupeptin using a cryptic biosynthetic gene cluster of the myxobacterium Melittangium boletus.

Myxobacteria have comparatively large genomes that contain many biosynthetic genes with the potential to produce secondary metabolites. Based on genome mining, we discovered a new biosynthetic gene cluster of class III lanthipeptide in the genome of the myxobacterium Melittangium boletus. The biosynthetic gene cluster contained a precursor peptide-coding gene bolA, and a class III lanthipeptide synthetase-coding gene bolKC. The expression vector containing bolA and bolKC was constructed using synthetic DNA with codon-optimized sequences based on the commercially available vector pET29b. Co-expression of the two genes in the host Escherichia coli BL21(DE3) yielded a new class III lanthipeptide named boletupeptin. The structure of boletupeptin was proposed to have one unit of labionin, as determined by mass spectrometry experiments after reductive cleavage. This is the first report of a class III lanthipeptide from a myxobacterial origin.

Measurement of luteinizing hormone surge in vaginal discharge: a potential biomarker that enables simple, non-invasive prediction of the periovulatory period.

BACKGROUND: Predicting the periovulatory period is very important for conception. Current approaches to predicting the periovulatory period include monitoring of basal body temperature and urine luteinizing hormone (LH) concentration; however, these methods are time-consuming. Here, we examined the potential of using vaginal discharge (VD) as a non-invasive means of sample collection for determining the LH surge that indicates ovulation. METHODS: Urine and VD samples were collected from 35 healthy women aged 20-39 years. VD samples were collected with panty liners to reduce the burden on participants. Daily first urine samples and used panty liners were collected from the 10th through 19th days of the menstrual cycle. Urine and VD LH (uLH and vLH) levels in the samples were measured by enzyme-linked immunosorbent assay. Measured vLH baseline and first surge values were analyzed using Student's t-test and ROC curves. RESULTS: Samples for a total of 55 menstrual cycles were collected. We used uLH surge to establish the date of ovulation. uLH surges were observed in 49 cycles, 34 of which had corresponding VD samples that qualified for measurement. Five cycles were excluded due to a lack of vLH data. In the remaining 29 cycles, the vLH surge appeared within the fertile window 90% of the time, and the sensitivity and specificity of the test were 86% and 83%, respectively. CONCLUSIONS: VD has potential for use as a sample for predicting the periovulatory period by measuring LH content.

Hepatic glucuronidation of tetrabromobisphenol A and tetrachlorobisphenol A: interspecies differences in humans and laboratory animals and responsible UDP-glucuronosyltransferase isoforms in humans.

Tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA), bisphenol A (BPA) analogs, are endocrine-disrupting chemicals predominantly metabolized into glucuronides by UDP-glucuronosyltransferase (UGT) enzymes in humans and rats. In the present study, TBBPA and TCBPA glucuronidation by the liver microsomes of humans and laboratory animals (monkeys, dogs, minipigs, rats, mice, and hamsters) and recombinant human hepatic UGTs (10 isoforms) were examined. TBBPA glucuronidation by the liver microsomes followed the Michaelis-Menten model kinetics in humans, rats, and hamsters and the biphasic model in monkeys, dogs, minipigs, and mice. The CLint values based on the Eadie-Hofstee plots were mice (147) > monkeys (122) > minipigs (108) > humans (100) and rats (98) > dogs (81) > hamsters (47). TCBPA glucuronidation kinetics by the liver microsomes followed the biphasic model in all species except for minipigs, which followed the Michaelis-Menten model. The CLint values were monkeys (172) > rats (151) > mice (134) > minipigs (104), dogs (102), and humans (100) > hamsters (88). Among recombinant human UGTs examined, UGT1A1 and UGT1A9 showed higher TBBPA and TCBPA glucuronidation abilities. The kinetics of TBBPA and TCBPA glucuronidation followed the substrate inhibition model in UGT1A1 and the Michaelis-Menten model in UGT1A9. The CLint values were UGT1A1 (100) > UGT1A9 (42) for TBBPA glucuronidation and UGT1A1 (100) > UGT1A9 (53) for TCBPA glucuronidation, and the activities at high substrate concentration ranges were higher in UGT1A9 than in UGT1A1 for both TBBPA and TCBPA. These results suggest that the glucuronidation abilities toward TBBPA and TCBPA in the liver differ extensively across species, and that UGT1A1 and UGT1A9 expressed in the liver mainly contribute to the metabolism and detoxification of TBBPA and TCBPA in humans.

Slip of a liquid crystal droplet rotator in viscous fluids.

Microscale flow plays an important role in several areas, including microbiological systems and microfluidic devices. These systems are often placed in viscous or complex fluids such as polymer solutions. Understanding microscale flow in viscous fluids will lead to a further development of microfluidic devices and elucidation of the collective motion of microorganisms. We studied the microscale flow induced by the optically driven rotation of a nematic liquid crystal (NLC) droplet in an aqueous glycerol solution. The rotation of the droplets was controlled using circularly polarized optical tweezers. In water, the induced flow agrees well with the theoretical flow assuming a solid rotating particle and a no-slip boundary condition. However, the induced flow velocity deviated from the theoretical value as the viscosity of the glycerol solution increased. This deviation was mainly due to slip on the droplet surface. As an application of the NLC rotator, the viscosity of the solutions and the hydrodynamic interactions between the two rotating particles were measured.

In vivo deuterium magnetic resonance imaging of xenografted tumors following systemic administration of deuterated water.

In vivo deuterated water (2H2O) labeling leads to deuterium (2H) incorporation into biomolecules of proliferating cells and provides the basis for its use in cell kinetics research. We hypothesized that rapidly proliferating cancer cells would become preferentially labeled with 2H and, therefore, could be visualized by deuterium magnetic resonance imaging (dMRI) following a brief period of in vivo systemic 2H2O administration. We initiated systemic 2H2O administration in two xenograft mouse models harboring either human colorectal, HT-29, or pancreatic, MiaPaCa-2, tumors and 2H2O level of ~ 8% in total body water (TBW). Three schemas of 2H2O administration were tested: (1) starting at tumor seeding and continuing for 7 days of in vivo growth with imaging on day 7, (2) starting at tumor seeding and continuing for 14 days of in vivo growth with imaging on day 14, and (3) initiation of labeling following a week of in vivo tumor growth and continuing until imaging was performed on day 14. Deuterium chemical shift imaging of the tumor bearing limb and contralateral control was performed on either day 7 of 14 after tumor seeding, as described. After 14 days of in vivo tumor growth and 7 days of systemic labeling with 2H2O, a clear deuterium contrast was demonstrated between the xenografts and normal tissue. Labeling in the second week after tumor implantation afforded the highest contrast between neoplastic and healthy tissue in both models. Systemic labeling with 2H2O can be used to create imaging contrast between tumor and healthy issue, providing a non-radioactive method for in vivo cancer imaging.

Drug-induced entero-colitis due to interleukin-17 inhibitor use; capsule endoscopic findings and pathological characteristics: A case report.

BACKGROUND: Interleukin-17 (IL-17) inhibitors are known to cause exacerbation or new onset of inflammatory bowel disease upon administration. However, few reports have described characteristic endoscopic and histopathologic findings, and no small intestinal lesions have been reported so far. CASE SUMMARY: A woman in her 60s with psoriasis was administered ixekizumab (IXE), an anti-IL-17A antibody, for the treatment of psoriasis. Twenty months after commencing treatment, the patient visited our hospital because of persistent diarrhea. Blood tests performed at the time of the visit revealed severe inflammation, and colonoscopy revealed multiple round ulcers throughout the colon. A tissue biopsy of the ulcer revealed infiltration of inflammatory cells and granuloma-like findings in the submucosal layer. Capsule endoscopy revealed multiple jejunal erosions. After the withdrawal of IXE, the symptoms gradually improved, and ulcer reduction and scarring of the colon were endoscopically confirmed. CONCLUSION: To the best of our knowledge, 17 reports have documented IL-17 inhibitor-induced entero-colitis with endoscopic images, endoscopic findings, and pathological characteristics, including the present case. Nine of these cases showed diffuse loss of vascular pattern, coarse mucosa/ulcer formation in the left colon, and endoscopic findings similar to those of ulcerative colitis. In the remaining eight cases, discontinuous erosions and ulcerations from the terminal ileum to the rectum were seen, with endoscopic findings similar to those of Crohn's disease. In this case, the findings were confirmed by capsule endoscopy, which has not been previously reported.

Closed-Loop Recyclable Poly(imine-acetal)s with Dual-Cleavable Bonds for Primary Building Block Recovery.

Chemical recycling offers a promising solution for the end-of-life treatment of synthetic polymers. However, the efficient recovery of well-defined recycled building blocks continues to be a major challenge, especially for crosslinked thermosets. Here, we developed vanillin-based polymer networks functionalized with dual-cleavable imine and acetal bonds that facilitate chemical recycling to primary building blocks and their convenient separation at the molecular level. A library of crosslinked poly(imine-acetal)s was synthesized by combining the in-bulk synthesized liquid di-vanillin acetal monomer (DVA) with commercially available liquid di- and triamines under solvent-free conditions. These thermosets showed tailor-made thermal and mechanical properties along with outstanding chemical recyclability. Under aqueous acidic conditions, poly(imine-acetal)s selectively and completely disintegrate into small molecules. During the polymer design stage, these compounds were carefully selected to enable facile separation without tedious techniques. As a result, the primary building blocks were isolated in high yields and purity and immediately reused to produce fresh polymers with identical thermomechanical properties. Since our "design for recycling" concept aims at obtaining the primary building blocks rather than monomers after depolymerization, a plethora of possibilities are unlocked to utilize these chemical resources, including closed-loop recycling as portrayed.

Heterologous Production and Structure Determination of a New Lanthipeptide Sinosporapeptin Using a Cryptic Gene Cluster in an Actinobacterium Sinosporangium siamense.

Lipolanthine is a subclass of lanthipeptide that has the modification of lipid moiety at the N-terminus. A cryptic biosynthetic gene cluster comprising four genes (sinA, sinKC, sinD, and sinE) involved in the biosynthesis of lipolanthine was identified in the genome of an actinobacterium Sinosporangium siamense. Heterologous coexpression of a precursor peptide coding gene sinA and lanthipeptide synthetase coding gene sinKC in the host Escherichia coli strain BL21(DE3) resulted in the synthesis of a new lanthipeptide, sinosporapeptin. It contained unusual amino acids, including one labionin and two dehydrobutyrine residues, as determined using NMR and MS analyses. Another coexpression experiment with two additional genes of decarboxylase (sinD) and N-acetyl transferase (sinE) resulted in the production of a lipolanthine-like modified sinosporapeptin.

EPR and Related Magnetic Resonance Imaging Techniques in Cancer Research.

Imaging tumor microenvironments such as hypoxia, oxygenation, redox status, and/or glycolytic metabolism in tissues/cells is useful for diagnostic and prognostic purposes. New imaging modalities are under development for imaging various aspects of tumor microenvironments. Electron Paramagnetic Resonance Imaging (EPRI) though similar to NMR/MRI is unique in its ability to provide quantitative images of pO2 in vivo. The short electron spin relaxation times have been posing formidable challenge to the technology development for clinical application. With the availability of the narrow line width trityl compounds, pulsed EPR imaging techniques were developed for pO2 imaging. EPRI visualizes the exogenously administered spin probes/contrast agents and hence lacks the complementary morphological information. Dynamic nuclear polarization (DNP), a phenomenon that transfers the high electron spin polarization to the surrounding nuclear spins (1H and 13C) opened new capabilities in molecular imaging. DNP of 13C nuclei is utilized in metabolic imaging of 13C-labeled compounds by imaging specific enzyme kinetics. In this article, imaging strategies mapping physiologic and metabolic aspects in vivo are reviewed within the framework of their application in cancer research, highlighting the potential and challenges of each of them.

Stereotactic radiosurgery for recurrent pleomorphic adenoma of the lacrimal gland: a case report.

Lacrimal gland pleomorphic adenomas (LGPAs) are common, benign, and intraorbital tumours that cause exophthalmos, ptosis, and visual disturbances. The curative treatment for LGPAs is gross total resection, and radiotherapy is considered adjunctive for recurrence or an alternative for inoperable LGPAs. Stereotactic radiosurgery (SRS) can be used for precise delivery of high radiation doses to the tumour, crucial in the treatment of intra-and extracranial neoplasms. Here, we present a 95-year-old woman who had a rapidly growing, recurrent LGPA and was successfully treated with SRS. The tumour was controlled without any adverse events over 21 months following SRS. SRS is a potential alternative treatment for recurrent LGPA.

Predictive model for bleeding after gastric submucosal dissection before and after guidelines: A single-center retrospective study.

Objectives: In July 2017, supplementary guidelines on anticoagulants, including direct oral anticoagulants, were published in Japan. We investigated the changes in endoscopic submucosal dissection (ESD) of gastric mucosal lesions after the publication of the supplement, examined the risk factors, and developed a predictive model for post-ESD bleeding. Methods: We included 2272 gastric ESD cases from our hospital between May 2003 and June 2021 and classified them into two groups: 1789 cases before and 483 after the publication of the supplementary guidelines. A predictive model for post-ESD bleeding was developed using the pre-publication cohort data. Results: The proportion of patients receiving warfarin decreased (5.0% vs. 1.4%) and those receiving direct oral anticoagulants increased (1.2% vs. 6.8%) after the publication of the supplementary guidelines. Post-ESD bleeding occurred in 61 patients, but there was no significant difference in the bleeding rate between the groups (50 [2.8%] vs. 11 [2.3%] patients, respectively). Five risk factors (number of antithrombotic agents, dialysis, heparin replacement, resection specimen size, and procedure time) were identified for model development. The C-statistic for the model and post-publication cohorts were 0.83 and 0.72, respectively. In the model, each risk factor for postoperative bleeding was scored, and the risk was classified into three levels according to the total score. Bleeding rates at low, intermediate, and high risks were 1.6%, 10.3%, and 38.9%, respectively. Conclusion: Despite changes in patient characteristics and clinical practice regarding ESD before and after the publication of the supplementary guidelines, we could still develop a simple and useful predictive model.

Optically driven liquid crystal droplet rotator.

In this study, the rotation of liquid crystal droplets induced by elliptically polarized laser light was investigated using optical tweezers. The rotation mechanism was analyzed based on the arrangement of liquid crystal molecules within the droplets. The change in the rotation behavior of nematic liquid crystal (NLC) droplets was evaluated by varying the droplet size. The experimental results were analyzed based on the waveplate effect and light-scattering process. The rotation behavior of cholesteric liquid crystal droplets was examined by varying the droplet size and helical pitch, which was controlled by the chiral dopant concentration. The results are discussed in terms of the selective reflection of the incident beam by the helical structure. The dependence of the rotation frequency on the ellipticity of the incident beam was also studied. The main contribution to the rotation gradually changes from light transmission to reflection with increasing chirality of the droplet. An NLC rotator system was constructed using holographic optical tweezers. Such an optically controllable rotator is a typical micro-optomechanical device. Complex flow fields, including multiple vortex and localized shear fields, were realized at the micron scale.

Closed-Loop Recycling of Poly(Imine-Carbonate) Derived from Plastic Waste and Bio-based Resources.

Closed-loop recycling of polymers represents the key technology to convert plastic waste in a sustainable fashion. Efficient chemical recycling and upcycling strategies are thus highly sought-after to establish a circular plastic economy. Here, we present the selective chemical depolymerization of polycarbonate by employing a vanillin derivative as bio-based feedstock. The resulting di-vanillin carbonate monomer was used in combination with various amines to construct a library of reprocessable poly(imine-carbonate)s, which show tailor-made thermal and mechanical properties. These novel poly(imine-carbonate)s exhibit excellent recyclability under acidic and energy-efficient conditions. This allows the recovery of monomers in high yields and purity for immediate reuse, even when mixed with various commodity plastics. This work provides exciting new insights in the design of bio-based circular polymers produced by upcycling of plastic waste with minimal environmental impact.

Continuous monitoring of postirradiation reoxygenation and cycling hypoxia using electron paramagnetic resonance imaging.

Reoxygenation has a significant impact on the tumor response to radiotherapy. With developments in radiotherapy technology, the relevance of the reoxygenation phenomenon in treatment efficacy has been a topic of interest. Evaluating the reoxygenation in the tumor microenvironment throughout the course of radiation therapy is important in developing effective treatment strategies. In the current study, we used electron paramagnetic resonance imaging (EPRI) to directly map and quantify the partial oxygen pressure (pO2 ) in tumor tissues. Human colorectal cancer cell lines, HT29 and HCT116, were used to induce tumor growth in female athymic nude mice. Tumors were irradiated with 3, 10, or 20 Gy using an x-ray irradiator. Prior to each EPRI scan, magnetic resonance imaging (MRI) was performed to obtain T2-weighted anatomical images for reference. The differences in the mean pO2 were determined through two-tailed Student's t-test and one-way analysis of variance. The median pO2 60 min after irradiation was found to be lower in HCT116 than in HT29 (9.1 ± 1.5 vs. 14.0 ± 1.0 mmHg, p = 0.045). There was a tendency for delayed and incomplete recovery of pO2 in the HT29 tumor when a higher dose of irradiation (10 and 20 Gy) was applied. Moreover, there was a dose-dependent increase in the hypoxic areas (pO2  < 10 mmHg) 2 and 24 h after irradiation in all groups. In addition, an area that showed pO2 fluctuation between hypoxia and normoxia (pO2  > 10 mmHg) was also identified surrounding the region with stable hypoxia, and it slightly enlarged after recovery from acute hypoxia. In conclusion, we demonstrated the reoxygenation phenomenon in an in vivo xenograft model study using EPRI. These findings may lead to new knowledge regarding the reoxygenation process and possibilities of a new radiation therapy concept, namely, reoxygenation-based radiation therapy.

A case of severe acute hemorrhagic duodenitis after administration of immune checkpoint inhibitor.

Case: A 66-year-old man started carboplatin + etoposide + atezolizumab therapy for advanced small cell lung cancer. Seventeen days after the start of treatment, the patient presented with hematemesis and underwent emergency endoscopy, which revealed multiple erosions and ulcers in the duodenum. Some ulcers showed pulsating bleeding, which was stopped by clipping and cauterization using hemostats. Biopsy of the mucosal peri-ulcer showed lymphocyte, eosinophil, and plasma cell infiltration. The patient was suggested to have acute hemorrhagic duodenitis, which was associated with immune checkpoint inhibitors (ICIs), and conservative treatment with blood transfusion and antacids was continued. However, 11 days after hemostasis, bleeding from a new ulcer was observed. Hemostasis was achieved by coagulation and clipping again, but the general condition of the patient deteriorated owing to the rapid progression of the primary disease, and he died 8 weeks after the start of treatment. Discussion: Although there have been several reports of colitis and other adverse events caused by ICIs, there have been very few reports of duodenitis. Endoscopic findings include diffuse erythema, erosions/ulcerations, and villous atrophy, and pathological findings include eosinophilic infiltration and increased levels of CD8-positive T cells. However, there have been no reports of duodenal mucosal damage caused after administration of atezolizumab nor of severe cases of massive bleeding requiring endoscopic hemostasis and blood transfusion, as in this case.

Temporal observation of endoscopic and histological findings of gastritis after administration of an immune checkpoint inhibitor: a case report.

A 71-year-old Japanese man was treated with 200 mg of pembrolizumab for lung adenocarcinoma with multiple bone metastases at the Department of Respiratory Medicine of Kameda General Hospital. After 19 treatment courses, he complained of epigastric pain before meals. Upper gastrointestinal endoscopy showed multiple erosions in the gastric antrum, and antacids were administered at follow-up. After 27 treatment courses, the patient underwent another endoscopy because of anorexia. The erosions were enlarged and had increased from the gastric antrum to the greater curvature of the body. Histological biopsy showed lymphocytic infiltration with a predominance of CD8-positive T cells. The patient had previously been treated for Helicobacter pylori infection, and we suspected drug-induced gastritis due to the administration of immune checkpoint inhibitors in the course of the disease. Pembrolizumab was discontinued, and the patient's symptoms gradually improved. Endoscopic examinations were performed 2, 5, and 9 months after discontinuation of pembrolizumab, and improvement in mucosal findings and decreased lymphocyte infiltration were confirmed each time. The patient has remained without any relapse of symptoms for more than 1 year after discontinuing treatment.

[Isolated central nervous system relapse of Philadelphia chromosome-positive acute lymphoblastic leukemia during ponatinib maintenance therapy].

A 65-year-old man was diagnosed with Philadelphia chromosome-positive acute lymphoblastic leukemia with no initial central nervous system (CNS) involvement. Complete remission was achieved after the induction therapy. However, during consolidation therapy, he developed septic shock and pneumocystis pneumonia, leading to interruption in chemotherapy and allogeneic transplantation. Subsequently, he achieved complete molecular remission and ponatinib maintenance therapy was initiated. Two years later, he developed left leg paralysis and was diagnosed with isolated CNS relapse; however, radiation therapy improved CNS lesions and paralysis. Thus, ponatinib maintenance therapy alone is inadequate in preventing CNS relapse in patients who have not completed systemic chemotherapy for CNS relapse prevention.

Headspace Solid-Phase Microextraction/Gas Chromatography-Mass Spectrometry for the Determination of 2-Nonenal and Its Application to Body Odor Analysis.

The odors and emanations released from the human body can provide important information about the health status of individuals and the presence or absence of diseases. Since these components often emanate from the body surface in very small quantities, a simple sampling and sensitive analytical method is required. In this study, we developed a non-invasive analytical method for the measurement of the body odor component 2-nonenal by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry by selective ion monitoring. Using a StableFlex PDMS/DVB fiber, 2-nonenal was efficiently extracted and enriched by fiber exposition at 50 °C for 45 min and was separated within 10 min using a DB-1 capillary column. Body odor sample was easily collected by gauze wiping. The limit of detection of 2-nonenal collected in gauze was 22 pg (S/N = 3), and the linearity was obtained in the range of 1-50 ng with a correlation coefficient of 0.991. The method successfully analyzed 2-nonenal in skin emissions and secretions and was applied to the analysis of body odor changes in various lifestyles, including the use of cosmetics, food intake, cigarette smoking, and stress load.

Real-Time insight into in vivo redox status utilizing hyperpolarized [1-13C] N-acetyl cysteine.

Drastic sensitivity enhancement of dynamic nuclear polarization is becoming an increasingly critical methodology to monitor real-time metabolic and physiological information in chemistry, biochemistry, and biomedicine. However, the limited number of available hyperpolarized 13C probes, which can effectively interrogate crucial metabolic activities, remains one of the major bottlenecks in this growing field. Here, we demonstrate [1-13C] N-acetyl cysteine (NAC) as a novel probe for hyperpolarized 13C MRI to monitor glutathione redox chemistry, which plays a central part of metabolic chemistry and strongly influences various therapies. NAC forms a disulfide bond in the presence of reduced glutathione, which generates a spectroscopically detectable product that is separated from the main peak by a 1.5 ppm shift. In vivo hyperpolarized MRI in mice revealed that NAC was broadly distributed throughout the body including the brain. Its biochemical transformation in two human pancreatic tumor cells in vitro and as xenografts differed depending on the individual cellular biochemical profile and microenvironment in vivo. Hyperpolarized NAC can be a promising non-invasive biomarker to monitor in vivo redox status and can be potentially translatable to clinical diagnosis.