Strain typing and antimicrobial susceptibility of Salmonella enterica Albany isolates from duck farms in South Korea.

Salmonella enterica is distributed worldwide and is a common cause of bacterial food poisoning in humans and a serious public health problem. Although duck meat consumption has recently increased in Korea, studies on the epidemiological relationship between S. enterica contamination in duck farms are scarce. Salmonella enterica serovar Albany isolates recovered from duck farms were analyzed using two typing methods - IR Biotyper® (IRBT) and multilocus variable-number tandem repeat analysis (MLVA). The clustering results were compared with the epidemiological survey findings and the antimicrobial resistance profiles. From April 2019 to October 2020, 20 individual feces per farm from 5-6-week-old ducks were collected repeatedly from 105 duck farms. Salmonella spp. isolated from duck feces were identified using PCR and multilocus sequence typing to investigate the prevalence and distribution of the Salmonella serovars. The prevalence of S. enterica was 19%, and S. enterica Albany was the predominantly recovered isolate. The S. enterica Albany isolates underwent antimicrobial susceptibility testing to determine the minimum inhibitory concentration. MLVA and IRBT methods established relatedness and diversity among the S. enterica Albany isolates. Multidrug-resistant S. enterica Albany was distributed in all the farms. Antimicrobial resistance profiles reflected the duck farm characteristics and isolates recovered from the same farm showed an identical profile. Isolates repeatedly recovered from the same farm also showed identical IRBT clusters and MLVA groups. These findings suggest that the isolates remained on the duck farm and re-infected new duck flocks. Thus, proper cleaning and disinfection is required before the farms are repopulated.

Genetic trends in parrot Bornavirus: a clinical analysis.

Parrot Bornavirus (PaBV) has been reported to cause indigestion and other wasting symptoms such as weight loss and lethargy. The pathogenesis of PaBV has yet to be fully elucidated. This study reports PaBV infections in South Korea and suggests a trend in the genetic information gathered from clinical cases. A total of 487 birds with or without clinical symptoms were tested for bornavirus. Twelve of 361 asymptomatic birds tested positive for bornavirus, while 15 of 126 birds with various symptoms tested positive. A segment of approximately 1,540 bps including the N, X, P and M proteins were obtained from 23 of the positive strains and analyzed with other strains found on GenBank that had clinical information. PaBV was type 2 and 4 in South Korea, and certain amino acid sequences showed a difference between symptom presenting animals and asymptomatic animals in the X protein and P protein. When considering that some asymptomatic cases may have been latent infections at the time of examination, it is plausible these trends may grow stronger with time. Majority of PaBV was type 4 in South Korea. If these trends are confirmed, diagnosis of potentially pathogenic PaBVs in a clinical manner will be possible during the early stages of infection.

Assessment of fungal contamination and biosecurity risk factors in duck-breeding farms in South Korea.

Fungi are pathogens that infect all types of poultry and farmers, leading to economic losses in poultry production. Fungi can be isolated from environmental samples and are ubiquitous in the air. This study aimed to evaluate fungal contamination in domestic duck farm environments and analyze biosecurity risk factors associated with fungal infection incidence to assess the vulnerability of the farms to fungal infection. The average fungal concentration was 203 colony-forming units (CFU)/m3 in the air and 365 × 103 CFU/m2 in the wall surface samples. Sixteen fungal genera were recovered from air and wall surface samples from 19 duck-breeding farms, Aspergillus being the most frequently isolated (air: 43.2%; wall surface: 40%). Eleven additional fungal genera (Acrophialophora, Byssochlamys, Fusarium, Lichtheimia, Paecilomyces, Penicillium, Polycephalomyces, Rhizomucor, Scopulariopsis, Talaromyces, and Thermoascus) were isolated from air samples. Also, 8 additional fungal genera (Chaetomium, Lichtheimia, Penicillium, Petriella, Rhizomucor, Rhizopus, Talaromyces, and Trichosporon) were isolated from wall surface samples. The characteristics of the poultry farms (geographic region, stocking density, breeding house type, affiliate, duck age, and season) and fungal concentrations in the air and wall surface samples were analyzed to evaluate the biosecurity risk of the farms. Fungal infections were significantly affected by high stocking density (>2 ducks/m2), duck age (18-25 wk and >60 wk), and high fungal concentration in the wall surface samples (>300 × 103 CFU/m2).

A novel multiplex RT-qPCR assay for simultaneous detection of bovine norovirus, torovirus, and kobuvirus in fecal samples from diarrheic calves.

Calf diarrhea results in significant economic loss and is caused by a variety of pathogens, including enteric viruses. Many of these viruses, including bovine norovirus (BNoV), bovine torovirus (BToV), and bovine kobuvirus (BKoV), are recognized as the causative agents of diarrhea; however, they remain understudied as major pathogens. We developed a multiplex reverse-transcription quantitative real-time PCR (RT-qPCR) assay for rapid and simple detection of BNoV, BToV, and BKoV. Our method had high sensitivity and specificity, with detection limits of 1 × 102 copies/µL for BNoV, BToV, and BKoV, which is a lower detection limit than conventional RT-PCR for BNoV and BKoV and identical for BToV. We tested fecal samples from 167 diarrheic calves with our multiplex RT-qPCR method. Viral detection was superior to conventional RT-PCR methods in all samples. The diagnostic sensitivity of the multiplex RT-qPCR method (100%) is higher than that of the conventional RT-PCR methods (87%). Our assay can detect BNoV, BToV, and BKoV in calf feces rapidly and with high sensitivity and specificity.

CD19/CD22 bispecific chimeric antigen receptor­NK­92 cells are developed and evaluated.

Anti-CD19 chimeric antigen receptor (CAR)-T cells have improved the outcomes of patients with B cell leukemia and lymphoma. However, their applications and positive outcomes remain limited. CAR-T cells are currently restricted to autologous blood as their source and their use can lead to downregulation of CD19 expression along with complications such as graft-versus-host disease and cytokine release syndrome. The present study aimed to develop anti-CD19/CD22 bispecific CAR structures using an anti-CD22 monoclonal antibody clone from chickens and analyze them in natural killer (NK)-92 cells, a human NK cell line, in vitro and in vivo. Anti-CD19/CD22 CAR-NK-92 cell cytotoxicity was assessed by the survival of target cells and counted using flow cytometry. Anti-CD22/CD19 and loop-structured anti-CD19/CD22 bi-specific CAR-NK-92 cells showed improved efficacy against OCI-Ly7 cells, a human B cell lymphoma cell line, compared with other CAR structures. These results demonstrate the potential of anti-CD19/CD22 bispecific CAR-NK cells and suggested that optimizing CAR structures in NK cells can improve the efficacy of CAR therapy.

Role of Sterically Bulky Azobenzenes in the Molecular Assembly of Pyrene Derivatives: Rectangular Sheet-like Structures and Their Emission Characteristics.

The development of pyrene-based fluorescent assembled systems with desirable emission characteristics by reducing conventional concentration quenching and/or aggregation-induced quenching (ACQ) is highly desirable. In this investigation, we designed a new azobenzene-functionalized pyrene derivative (AzPy) in which sterically bulky azobenzene is linked to pyrene. Absorption and fluorescence spectroscopic results before and after molecular assembly indicate that even in a dilute N,N-dimethylformamide (DMF) solution (~10 µM), AzPy molecules experienced significant concentration quenching, whereas the emission intensities of AzPy DMF-H2O turbid suspensions containing self-assembled aggregates were slightly enhanced and showed similar values regardless of the concentration. The shape and size of sheet-like structures, from incomplete flakes less than one micrometer in size to well-completed rectangular microstructures, could be adjusted by changing the concentration. Importantly, such sheet-like structures exhibit concentration dependence of their emission wavelength from blue to yellow-orange. Comparison with the precursor (PyOH) demonstrates that the introduction of a sterically twisted azobenzene moiety plays an important role in converting the spatial molecular arrangements from H- to J-type aggregation mode. Thus, AzPy chromophores grow into anisotropic microstructures through inclined J-type aggregation and high crystallinity, which are responsible for their unexpected emission characteristics. Our findings provide useful insight into the rational design of fluorescent assembled systems.

Cytotoxicity of Human Hepatic Intrasinusoidal Gamma/Delta T Cells Depends on Phospho-antigen and NK Receptor Signaling.

BACKGROUND/AIM: We previously showed that human hepatic intrasinusoidal (HI) natural killer (NK) T cells selectively eliminate hepatocellular carcinoma (HCC) cell lines. In this study, we investigated the underlying mechanisms on how HI γδ T cells, expanded with zoledronate, exhibit a superior cytotoxic effect on HI NK-resistant Huh7 HCC cells. MATERIALS AND METHODS: γδ T cells were obtained from living liver transplant donors or from peripheral blood mononuclear cells (PBMC) of healthy volunteers and were expanded in the presence of IL-2, IL-15, and zoledronate for 2 weeks. Cytotoxicity was measured using the lactate dehydrogenase (LDH) assay in vitro and by flow cytometry using carboxyfluorescein succinimidyl ester (CFSE) in vivo. RESULTS: The cytotoxicity of expanded HI γδ T cells against Huh7 cells was associated with a higher pyrophosphate expression in Huh7 cells compared to SNU398 cells. In contrast, the cytotoxicity of HI γδ T cells against SNU398 cells depended on NKG2D. HI γδ T cells expressed less PD-1 than PB γδ T cells. The cytotoxicity of HI γδ T cells against Du145 and PC3 prostate cancer cells was also associated with pyrophosphate expression in these cells, as well as NKG2D and DNAM-1. CONCLUSION: The expression levels of phospho-antigen in tumor cells determined the cytotoxicity of HI γδ T cells, although the NK activating receptors, death ligands, and immune checkpoint molecules also contribute to their cytotoxicity. γδ T cells are attractive candidates for cancer immune cell therapy.

Light-Responsive Hexagonal Assemblies of Triangular Azo Dyes.

The rational design of small building block molecules and understanding their molecular assemblies are of fundamental importance in creating new stimuli-responsive organic architectures with desired shapes and functions. Based on the experimental results of light-induced conformational changes of four types of triangular azo dyes with different terminal functional groups, as well as absorption and fluorescence characteristics associated with their molecular assemblies, we report that aggregation-active emission enhancement (AIEE)-active compound (1) substituted with sterically crowded tert-butyl (t-Bu) groups showed approximately 35% light-induced molecular switching and had a strong tendency to assemble into highly stable hexagonal structures with AIEE characteristics. Their sizes were regulated from nanometer-scale hexagonal rods to micrometer-scale sticks depending on the concentration. This is in contrast to other triangular compounds with bromo (Br) and triphenylamine (TPA) substituents, which exhibited no photoisomerization and tended to form flexible fibrous structures. Moreover, non-contact exposure of the fluorescent hexagonal nanorods to ultraviolet (UV) light led to a dramatic hexagonal-to-amorphous structure transition. The resulting remarkable variations, such as in the contrast of microscopic images and fluorescence characteristics, were confirmed by various microscopic and spectroscopic measurements.

Evaluation of Biomechanical Properties and Morphometric Structures of the Trachea in Pigs and Rabbits.

BACKGROUND/AIM: Animals differ in the biochemical composition, attachments, and mechanical properties of tracheal cartilage. This study examined the biomechanical properties and morphological structure of the trachea of pigs, and rabbits as preclinical models. MATERIALS AND METHODS: The trachea in pigs and rabbits can be divided into four regions, cranial cervical, middle cervical, thoracic inlet, and intra-thoracic parts. RESULTS: The total number of tracheal rings in pigs and rabbits was 32-35 and 34-38 rings, respectively. The pig bronchus first branches from the trachea, reaching the cranial lobe of the lungs before branching to the main bronchus, while the rabbit bronchus branched after the main bronchus. A comparison of the posterior region of the crosssectional trachea shows that the rabbit has a C-shape with cartilage connected to the tracheal muscle, and the pig has the tracheal muscle covered with cartilage. The trachea of pigs and rabbits decreased in tracheal thickness and size from the thoracic inlet toward the lungs. The stress-strain in the longitudinal and transverse tensile test was higher in rabbits than in pigs. The tensile stress of the four regions was significantly different in the transverse tensile test (p<0.001). In the bending test, more force was required to bend pig than rabbit tracheas. Microscopic and scanning electron microscopy showed no structural differences in tracheal cartilage between the two species. CONCLUSION: These results suggest that there is great variation in morphology and physical properties of the trachea in pigs and rabbits. We found porcine tracheas have similar biomechanical properties to those of humans.

Solvent- and Light-Sensitive AIEE-Active Azo Dye: From Spherical to 1D and 2D Assemblies.

Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials.

Curation of the CANDID-PTX Dataset with Free-Text Reports.

Supplemental material is available for this article. Keywords: Conventional Radiography, Thorax, Trauma, Ribs, Catheters, Segmentation, Diagnosis, Classification, Supervised Learning, Machine Learning © RSNA, 2021.

Characteristics of Human Peripheral Blood γδ T Cells Expanded With Zoledronate.

BACKGROUND/AIM: This study aimed to investigate the characteristics of human peripheral blood γδ T cells, which were expanded ex vivo in the presence of zoledronate (ZOL). MATERIALS AND METHODS: Human peripheral blood cells were cultured with IL-2 and IL-15 in the presence or absence of ZOL, which was added as a phospho-antigen, and their phenotypes were assessed by flow cytometry. Expanded γδ T cells were transduced with CD19 CAR vector, and the cytotoxicity was evaluated in vitro and in vivo by flow cytometry. RESULTS: Ex vivo expansion did not hamper the expression of activating receptors. Interestingly, ZOL promoted the expression of CD226 (DNAM-1), TRAIL, and FAS-L in the Vδ1 subset of γδ T cells. Expanded γδ T cells containing CD19 CAR+ γδ T cells removed B cell lymphoma cells effectively in vivo. CONCLUSION: γδ T cells could be a promising immunotherapeutic for cancer.

Morphologically Diverse Micro- and Macrostructures Created via Solvent Evaporation-Induced Assembly of Fluorescent Spherical Particles in the Presence of Polyethylene Glycol Derivatives.

The creation of fluorescent micro- and macrostructures with the desired morphologies and sizes is of considerable importance due to their intrinsic functions and performance. However, it is still challenging to modulate the morphology of fluorescent organic materials and to obtain insight into the factors governing the morphological evolution. We present a facile bottom-up approach to constructing diverse micro- and macrostructures by connecting fluorescent spherical particles (SPs), which are generated via the spherical assembly of photoisomerizable azobenzene-based propeller-shaped chromophores, only with the help of commercially available polyethylene glycol (PEG) derivatives. Without any extra additives, solvent evaporation created a slow morphological evolution of the SPs from short linear chains (with a length of a few micrometers) to larger, interconnected networks and sheet structures (ranging from tens to >100 µm) at the air-liquid interface. Their morphologies and sizes were significantly dependent on the fraction and length of the PEG. Our experimental results suggest that noncovalent interactions (such as hydrophobic forces and hydrogen bonding) between the amphiphilic PEG chains and the relatively hydrophobic SPs were weak in aqueous solutions, but play a crucial role in creating the morphologically diverse micro- and macrostructures. Moreover, short-term irradiation with visible light caused fast morphological crumpling and fluorescence switching of the obtained structures.

Evaluation of Immunosuppressive Therapy Use for Tracheal Transplantation with Trachea-Mimetic Bellows Scaffolds in a Rabbit Model.

The objective of this study was to evaluate the use of immunosuppressive therapy with high-dose cyclosporine, high-dose azathioprine, and a combination of low-dose cyclosporine and azathioprine after tracheal reconstruction by using a trachea-mimetic graft of polycaprolactone (PCL) bellows-type scaffold in a rabbit model. Twenty-four healthy New Zealand white rabbits were used in the study. All underwent circumferential tracheal replacement using tissue-engineered tracheal graft, prepared from PCL bellows scaffold reinforced with silicone ring, collagen hydrogel, and human turbinate mesenchymal stromal cell (hTMSC) sheets. The control group (Group 1) received no medication. The three experimental groups were given daily cyclosporine intramuscular doses of 10 mg/kg (Group 2), azathioprine oral doses of 5 mg/kg (Group 3), and azathioprine oral doses of 2.5 mg/kg plus cyclosporine intramuscular doses of 5 mg/kg (Group 4) for 4 weeks or until death. Group 1 had longer survival times compared to Group 2 or Group 3. Each group except for Group 1 experienced decreases in amount of nutrition and weight loss. In addition, compared with the other groups, Group 2 had significantly increased serum interleukin-2 and interferon-γ levels 7 days after transplantation. The results of this study showed that the administration of cyclosporine and/or azathioprine after tracheal transplantation had no beneficial effects. Furthermore, the administration of cyclosporine had side effects, including extreme weight loss, respiratory distress, and diarrhea. Therefore, cyclosporine and azathioprine avoidance may be recommended for tracheal reconstruction using a native trachea-mimetic graft of PCL bellows-type scaffold in a rabbit model.

Charged Polymer-Coated Separators by Atmospheric Plasma-Induced Grafting for Lithium-Ion Batteries.

A simple and fast method of atmospheric plasma-induced grafting was applied over a polyethylene membrane to enhance its performance as a separator for lithium-ion batteries. The process of grafting has formed a thin, durable, and uniform layer on the surface of the porous membrane. The charges of grafted polymers affected the performance of batteries in many ways besides the change of hydrophilicity. Negative charges in polymers improve the capacity retention of batteries and the uniformity of the SEI layer. On the other hand, the electrostatic attraction between different charges contributed to small increases of thermal stability and mechanical strength of separators. Polyampholyte was grafted by using the mixtures of monomers, and the composition of the grafted layer was optimized. The formation of stable uniform SEI layers and the marked improvement in capacity retention were observed in the full cell tests of the lithium battery with the polyampholyte-grafted separators when the polyampholyte has a negative net charge.

Assembly of an Achiral Chromophore into Light-Responsive Helical Nanostructures in the Absence of Chiral Components.

The chirality found in living organisms is one of unsolved mysteries on Earth. It is crucial to understand the manner in which small achiral molecules evolve into helical superstructures in the absence of chiral components because this process can provide important insights regarding the origin of chirality in nature. 1) the uncommon helical assembly of an achiral trigonal chromophore into helical nanostructures with aggregation-induced emission enhancement (AIEE) characteristics and 2) the tunability of the helical pitch and fluorescence intensity in response to light is reported. The Rietveld refinement of X-ray diffraction (XRD) patterns and the growth process suggest that a striking transformation from an achiral to an asymmetric molecule can occur as a result of specific interactions with certain solvents, presumably leading to the unique helical assembly. More importantly, exposure to UV or visible light promoted not only the formation of irregular helical structures with a wide range of pitch lengths but also an increase in fluorescence intensity.

Elucidation of Isomerization Pathways of a Single Azobenzene Derivative Using an STM.

The predominant pathway for the isomerization between cis- and trans-azobenzenes-either (i) inversion by the bending of an NNC bond or (ii) rotation by the torsion of two phenyl rings-continues to be a controversial topic. To elucidate each isomerization pathway, a strategically designed and synthesized azobenzene derivative was investigated on a Ag(111) surface. This was achieved by exciting the molecule with tunneling electrons from the tip of a scanning tunneling microscope (STM). Structural analyses of the molecularly resolved STM images reveal that both inversion and rotation pathways are available for isomerization on a metal surface and strongly depend on the initial adsorption structures of the molecule. On the basis of the potential energy diagrams for the isomerization, it is concluded that isomerization pathways on a metal surface are not simply related to the excited states.

Multistimuli-responsive azobenzene nanofibers with aggregation-induced emission enhancement characteristics.

A new azobenzene-based chromophore was synthesized to create one-dimensional (1D) nanofibers with aggregation-induced emission enhancement characteristics. The enhanced red fluorescence of the fibrous structures can be switched off via mechanical pressure, friction, or heat by pressing, rubbing, or annealing.

Calix[4]tetrahydrothiophenopyrrole: a ditopic receptor displaying a split personality for ion recognition.

A calix[4]pyrrole fused with 2,5-dihydrothiophene, possessing both a deep, π-electron-rich pocket upon anion binding and chelating ligands on the periphery, was developed. The receptor selectively forms an ion-pair complex with CsF through H-bonding and a cation-π interaction. In the process, it adopt a conformationally fixed cone conformation. The receptor displays exceptionally high affinity toward the Hg(II) ion and forms stable complexes while maintaining a rigid 1,3-alternate conformation. This metal ion-induced conformational locking is unprecedented in calix[4]pyrrole chemistry.

Light-responsive three-dimensional microstructures composed of azobenzene-based palladium complexes.

We describe not only fleeting assembly of photoisomerizable azobenzene-based palladium complexes into microstructured crystalline architectures but also their light-responsive functions. A transformation in the crystalline morphology from two-dimensional (2D) parallelogram-like sheets to three-dimensional (3D) cuboid- or rhombus-like structures was achieved by changing the solvent from tetrahydrofuran (THF) to acetone and N,N-dimethylformamide (DMF). The sizes of the structures, ranging from a few hundred nanometers to several hundred micrometers, were also modified by varying the complex concentration. In stark contrast to the very stable 2D sheets in the THF-H2O suspensions, exposure of 3D structures in polar DMF-H2O suspensions to ultraviolet (UV) light led to fast disassembly of the structures into isolated metal complexes and further dissociation of free azobenzene ligands from the complexes. In acetone-H2O suspensions, interestingly, disassembly of 3D cuboid-like structures into isolated complex components occurred upon exposure to UV light without further dissociation of azobenzene ligands from the palladium complexes. Considering the photoisomerization ability of the azobenzene-based palladium complex in common organic solvents, the π-stacking interactions that support 3D structures are likely to be sufficiently weak that they might be broken by the UV-induced trans-to-cis isomerization in more polar solvent mixtures. As a consequence, disassembly proceeded under UV light irradiation. Moreover, the effect of solvent polarity on the UV-assisted dissociation (in DMF-H2O) may be associated with the coordination ability of solvent molecules with the metal center.