Antifungal activity of aminopyrrolnitrin against Trichophyton verrucosum in a guinea pig model of dermatophytosis.

BACKGROUND: Dermatophytosis is a common and major public health concern worldwide. Despite the increasing availability of antifungal drugs, relapses and untreated cases of dermatophyte infections are reported. Therefore, novel antifungal agents are required. Aminopyrrolnitrin (APRN) shows promise for dermatophytosis treatment because of its antifungal activity. OBJECTIVES: This study aimed to assess the antifungal properties of APRN against Trichophyton verrucosum (T. verrucosum), in both laboratory settings and a guinea pig model. METHODS: The minimum inhibitory concentrations (MICs) of APRN and enilconazole against T. verrucosum were determined according to the CLSI M38 method. The skins of 16 male guinea pigs were infected with 1.0 × 108 conidia of T. verrucosum and the animals were grouped into sets of four: negative control group (NC) received normal saline; positive control group (PC) received 2 µg/mL of enilconazole; and APRN4 and APRN8 received 4 and 8 µg/mL of APRN, respectively. Clinical, mycological and histological efficacies were measured after 10 days. RESULTS: The MIC90 of APRN and enilconazole against T. verrucosum was 4 and 2 µg/mL, respectively. The clinical scores of PC, APRN4, and APRN8 were significantly lower than those of NC. Clinical and mycological efficacies were higher for APRN8, APRN4 and PC. No fungi were observed in the skin tissues of APRN4 and APRN8, while fungi were observed in 50% of the PC. CONCLUSION: APRN showed antifungal activity against T. verrucosum in vitro and in vivo and is a potential candidate for the treatment of dermatophytosis.

Green fluorescence protein-based content-mixing assay of SNARE-driven membrane fusion.

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediate intracellular membrane fusion by forming a ternary SNARE complex. A minimalist approach utilizing proteoliposomes with reconstituted SNARE proteins yielded a wealth of information pinpointing the molecular mechanism of SNARE-mediated fusion and its regulation by accessory proteins. Two important attributes of a membrane fusion are lipid-mixing and the formation of an aqueous passage between apposing membranes. These two attributes are typically observed by using various fluorescent dyes. Currently available in vitro assay systems for observing fusion pore opening have several weaknesses such as cargo-bleeding, incomplete removal of unencapsulated dyes, and inadequate information regarding the size of the fusion pore, limiting measurements of the final stage of membrane fusion. In the present study, we used a biotinylated green fluorescence protein and streptavidin conjugated with Dylight 594 (DyStrp) as a Föster resonance energy transfer (FRET) donor and acceptor, respectively. This FRET pair encapsulated in each v-vesicle containing synaptobrevin and t-vesicle containing a binary acceptor complex of syntaxin 1a and synaptosomal-associated protein 25 revealed the opening of a large fusion pore of more than 5 nm, without the unwanted signals from unencapsulated dyes or leakage. This system enabled determination of the stoichiometry of the merging vesicles because the FRET efficiency of the FRET pair depended on the molar ratio between dyes. Here, we report a robust and informative assay for SNARE-mediated fusion pore opening.

Dynamic light scattering analysis of SNARE-driven membrane fusion and the effects of SNARE-binding flavonoids.

Soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) proteins generate energy required for membrane fusion. They form a parallelly aligned four-helix bundle called the SNARE complex, whose formation is initiated from the N terminus and proceeds toward the membrane-proximal C terminus. Previously, we have shown that this zippering-like process can be controlled by several flavonoids that bind to the intermediate structures formed during the SNARE zippering. Here, our aim was to test whether the fluorescence resonance energy transfer signals that are observed during the inner leaflet mixing assay indeed represent the hemifused vesicles. We show that changes in vesicle size accompanying the merging of bilayers is a good measure of progression of the membrane fusion. Two merging vesicles with the same size D in diameter exhibited their hydrodynamic diameters 2D + d (d, intermembrane distance), 2D and 2D as membrane fusion progressed from vesicle docking to hemifusion and full fusion, respectively. A dynamic light scattering assay of membrane fusion suggested that myricetin stopped membrane fusion at the hemifusion state, whereas delphinidin and cyanidin prevented the docking of the vesicles. These results are consistent with our previous findings in fluorescence resonance energy transfer assays.

SNARE zippering is hindered by polyphenols in the neuron.

Fusion of synaptic vesicles with the presynaptic plasma membrane in the neuron is mediated by soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor (SNARE) proteins. SNARE complex formation is a zippering-like process which initiates at the N-terminus and proceeds to the C-terminal membrane-proximal region. Previously, we showed that this zippering-like process is regulated by several polyphenols, leading to the arrest of membrane fusion and the inhibition of neuroexocytosis. In vitro studies using purified SNARE proteins reconstituted in liposomes revealed that each polyphenol uniquely regulates SNARE zippering. However, the unique regulatory effect of each polyphenol in cells has not yet been examined. In the present study, we observed SNARE zippering in neuronal PC12 cells by measuring the fluorescence resonance energy transfer (FRET) changes of a cyan fluorescence protein (CFP) and a yellow fluorescence protein (YFP) fused to the N-termini or C-termini of SNARE proteins. We show that delphinidin and cyanidin inhibit the initial N-terminal nucleation of SNARE complex formation in a Ca(2+)-independent manner, while myricetin inhibits Ca(2+)-dependent transmembrane domain association of the SNARE complex in the cell. This result explains how polyphenols exhibit botulinum neurotoxin-like activity in vivo.

Transcriptome profiles of organ tissues from pigs experimentally infected with African swine fever virus in early phase of infection.

African swine fever, caused by African swine fever virus (ASFV), is a highly contagious and fatal disease that poses a significant threat to the global pig industry. The limited information on ASFV pathogenesis and ASFV-host interactions has recently prompted numerous transcriptomic studies. However, most of these studies have focused on elucidating the transcriptome profiles of ASFV-infected porcine alveolar macrophages in vitro. Here, we analyzed dynamic transcriptional patterns in vivo in nine organ tissues (spleen, submandibular lymph node, mesenteric lymph node, inguinal lymph node, tonsils, lungs, liver, kidneys, and heart) obtained from pigs in the early stages of ASFV infection (1 and 3 d after viremia). We observed rapid spread of ASFV to the spleen after viremia, followed by broad transmission to the liver and lungs and subsequently, the submandibular and inguinal lymph nodes. Profound variations in gene expression patterns were observed across all organs and at all time-points, providing an understanding of the distinct defence strategies employed by each organ against ASFV infection. All ASFV-infected organs exhibited a collaborative response, activating immune-associated genes such as S100A8, thereby triggering a pro-inflammatory cytokine storm and interferon activation. Functional analysis suggested that ASFV exploits the PI3K-Akt signalling pathway to evade the host immune system. Overall, our findings provide leads into the mechanisms underlying pathogenesis and host immune responses in different organs during the early stages of infection, which can guide further explorations, aid the development of efficacious antiviral strategies against ASFV, and identify valuable candidate gene targets for vaccine development.

Impact of rumen cannulation surgery on rumen microbiota composition in Hanwoo steers.

Rumen cannulation is a surgical technique used to collect rumen contents from ruminants. However, rumen cannulation surgery may potentially impact the composition of the rumen microbiota. This study aimed to examine the longitudinal alterations in the rumen microbiota composition of Hanwoo steers after cannulation surgery. In this study, eight Hanwoo steers were used; four steers underwent rumen cannulation surgery (cannulation group), while the remaining four were left intact (control group). Rumen samples were collected from all eight steers using the stomach tubing method on the day before surgery (day 0) and on postoperative days 1, 4, 7, 10, 14, 17, 21, 24, and 28, resulting in 80 samples (10 timepoints × 8 animals). The microbiota of all 80 samples were analyzed using 16S rRNA gene amplicon sequencing with Quantitative Insights into Microbial Ecology version 2 (QIIME2). There were no significant differences (p > 0.05) in all major phyla and most major genera representing at least 0.5% of total sequences across all 80 samples between the control and cannulation groups on the preoperative and postoperative days. However, while the alpha diversity indices did not differ (p > 0.05) between the two groups on the preoperative day, they significantly differed (p < 0.05) between the two groups on the postoperative days. Further, the overall microbial distribution based on both unweighted and weighted principal coordinate analysis plots significantly differed (p < 0.05) between the two groups on both the preoperative and postoperative days. Orthogonal polynomial contrasts indicated that major genera and microbial diversity in the cannulation group decreased following surgery but returned to their initial states by postoperative day 28. In conclusion, this study demonstrates that rumen cannulation surgery affects some major taxa and microbial diversity, suggesting that the rumen cannulation method can alter the composition of rumen microbiota in Hanwoo steers.

Exosomes isolation from bovine serum: qualitative and quantitative comparison between ultracentrifugation, combination ultracentrifugation and size exclusion chromatography, and exoEasy methods.

Exosomes have been extensively studied as disease biomarker in humans, given their role in transporting bioactive molecules. However, despite the great potential of exosomes as noninvasive diagnostic markers and therapeutic nanocarriers for bovine diseases, few studies have been conducted on bovine exosome. Thus, this study aimed to quantitatively and qualitatively compare three isolation methods to identify a suitable method for bovine serum. Exosomes were isolated using ultracentrifugation alone (UC), a combination of ultracentrifugation and size exclusion chromatography (US), or membrane affinity-based exoEasy kit (EE). Isolated particles were evaluated using a range of complementary techniques. Transmission electron microscopy showed that all three isolation methods resulted in particles with a cup-shaped morphology. The particle concentration measured by nanoparticle trafficking analyzer of US was lower compared to those of UC and EE method. As a result of immunoblotting, exosome markers including TSG101, CD81, and HSP70 were detected in US particles, while in UC and EE, only TSG101 expression was confirmed. Particles isolated from UC and EE showed a contamination with the blood protein albumin, whereas particles from US did not show albumin contamination. In addition, to evaluate the possibility of using exosomes as biomarkers, the profiles of the small RNA in the exosomes were compared using the bioanalyzer 2100. As a result, in the EE method, the band of small RNA (25-200 nt) was most prominent, and in the US methods, a distinct band was observed in the small RNA range. Collectively, the purity of exosomes without non-exosomal contamination was highest in the US method. However, for the detection of small RNA, the EE method was found to be the most suitable. Therefore, the results suggest that the optimal isolation method varies depending on the specific purpose of exosome isolation.

Modified t-butyl in tetradentate platinum (II) complexes enables exceptional lifetime for blue-phosphorescent organic light-emitting diodes.

In blue phosphorescent dopants, the tetradentate platinum(II) complex is a promising material showing high efficiency and stability in devices. However, metal-metal-to-ligand charge transfer (MMLCT) formation leads to low photo-luminescence quantum yields (PLQYs), wide spectra, and intermolecular interaction. To suppress MMLCT, PtON-tb-TTB and PtON-tb-DTB are designed using theoretical simulation by modifying t-butyl in PtON-TBBI. Both materials effectively suppress MMLCT and exhibit high PLQYs of 99% and 78% in 5 wt% doped film, respectively. The PtON-tb-TTB and PtON-tb-DTB devices have maximum external quantum efficiencies of 26.3% and 20.9%, respectively. Additionally, the PtON-tb-DTB device has an extended lifetime of 169.3 h with an initial luminescence of 1200 nit, which is 8.5 times greater than the PtON-TBBI device. Extended lifetime because of suppressed MMLCT and smaller displacement between the lowest triplet and triplet metal-centered states compared to other dopants. The study provides an effective approach to designing platinum(II) complexes for long device lifetimes.

Raw potato starch diet supplement in weaned pigs could reduce Salmonella Typhimurium infection by altering microbiome composition and improving immune status.

Backgorund: Salmonella enterica serovar Typhimurium (ST) is one of the causative agents of gastroenteritis in pigs. Pigs fed a diet supplemented with raw potato starch (RPS) have improved gut health by the alteration of the microbiota composition and production of short-chain fatty acids (SCFAs). This study aimed to evaluate the effects of RPS supplementation in reducing infection severity and fecal shedding in ST-infected pigs. Methods: The weaned experimental pigs were divided into two groups: CON (n = 6) fed a corn/soybean-based diet and TRT (n = 6) supplemented with 5% RPS. After 21 d, the pigs were inoculated with ST, and their body weight, clinical signs, and fecal shedding of ST were monitored for 14 d. At 14 d post-inoculation (dpi), the jejunum, cecum, ileum, and colon tissues were collected from euthanized pigs, and histopathological lesions and cytokine gene expression were compared. Additionally, blood samples at 2 dpi were analyzed for gene ontology enrichment. Moreover, the gutmicrobiome was analyzed using 16S rRNA metagenomic sequencing, and the SCFA concentration was measured using gas chromatography. Results: The average daily weight gain was significantly higher in TRT than in CON during the ST infection period; however, histopathological lesion scores were significantly lower in TRT than in CON. The relative abundance of nine genera of butyrate- and acetate-producing bacteria significantly increased in TRT compared with that of only two acetate-producing bacteria in CON. Among the genes involved in the immune response, IL-18 expression level was significantly lower in the jejunum and colon in TRT than in CON. Furthermore, Reg3γ expression was significantly different in the cecum and colon of both groups. Conclusion: The diet supplemented with RPS in weaned pigs could result in predominance of butyrate- and acetate-producing bacteria, reducing the severity of ST infection by improving the immune status.

Pathobiological analysis of african swine fever virus contact-exposed pigs and estimation of the basic reproduction number of the virus in Vietnam.

BACKGROUND: African swine fever (ASF), caused by African swine fever virus (ASFV), is a fatal disease affecting wild and domestic pigs. Since China reported the first ASF outbreak in August 2018, ASFV has swept over the neighbouring Asian countries. However, studies involving experimental pig-to-pig ASFV transmission in Vietnam are lacking. The main objective of this experimental study was to demonstrate the pathobiological characteristics of ASFV contact-exposed pigs and estimate their basic reproduction number (R0) in Vietnam. Fifteen pigs were randomly divided into two groups: experimental (n = 10) and negative control (n = 5) groups. One pig in the experimental group was intramuscularly inoculated with ASFV strain from Vietnam in 2020 and housed with the uninoculated pigs during the study period (28 days). RESULTS: The inoculated pig died 6 days post-inoculation, and the final survival rate was 90.0%. We started observing viremia and excretion of ASFV 10 days post-exposure in contact-exposed pigs. Unlike the surviving and negative control pigs, all necropsied pigs showed severe congestive splenomegaly and moderate-to-severe haemorrhagic lesions in the lymph nodes. The surviving pig presented with mild haemorrhagic lesions in the spleen and kidneys. We used Susceptible-Infectious-Removed models for estimating R0. The R0 values for exponential growth (EG) and maximum likelihood (ML) were calculated to be 2.916 and 4.015, respectively. In addition, the transmission rates (ß) were estimated to be 0.729 (95% confidence interval [CI]: 0.379-1.765) for EG and 1.004 (95% CI: 0.283-2.450) for ML. CONCLUSIONS: This study revealed pathobiological and epidemiological information in about pig-to-pig ASFV transmission. Our findings suggested that culling infected herds within a brief period of time may mitigate the spread of ASF outbreaks.

Multi-organ metastases of primary chondrosarcoma of the mammary gland of a spayed Toy Poodle.

We report the clinical and histopathological findings associated with multi-organ metastases of primary mammary chondrosarcoma in a 12-year-old spayed female Toy Poodle. At post-mortem examination, multifocal, sharply demarcated, grey-white to bright brown, round nodules of variable size were randomly distributed in the lungs, myocardium, liver, pancreas, spleen, intestinal tract and kidneys. Histologically, immature cartilage structures and primitive mesenchymal cells were seen in these organs. Neoplastic cells located in the cartilaginous basophilic extracellular matrix had cytoplasmic vacuolation and round vesicular nuclei and were stained with Safranin O and Alcian blue. To the best of our knowledge, this is the first report of a multi-organ metastatic chondrosarcoma that originated in the mammary gland of a dog.

Gut microbiota alteration with growth performance, histopathological lesions, and immune responses in Salmonella Typhimurium-infected weaned piglets.

Salmonella Typhimurium can cause gastroenteritis in weaned piglets, which are particularly vulnerable to dietary changes and dysfunction of their immature organs. The colonization of S. Typhimurium could disrupt the gut microbiota and increase susceptibility to the bacterium. This study aimed to investigate the alterations of gut microbiota in S. Typhimurium-infected weaned piglets. Ten 49-day-old pigs were divided into two groups: S. Typhimurium-inoculated (ST, n = 6) and negative control (NC, n = 4) groups. The body weight and S. Typhimurium fecal shedding were monitored for 14 days after S. Typhimurium inoculation (dpi). The intestinal tissues were collected at 14 dpi; histopathological lesions and cytokine gene expression were evaluated. The gut microbiome composition and short-chain fatty acid concentrations were analyzed in fecal samples collected at 14 dpi. The average daily gain and gut microbiota alpha diversity in ST group tended to be lower than NC group at 14 dpi. Linear discriminant analysis effect size results showed a significant increase in the abundance of two genera and five species, while a significant decrease was observed in the five genera and nine species within the gut microbiota of ST group. Among the significantly less abundant bacteria in the ST group, Lachnospira eligens and Anaerobium acetethylicum produce acetate and butyrate, and may be considered as key S. Typhimurium infection-preventing bacteria. The overall results provide invaluable information about changes in the gut microbiota of S. Typhimurium-infected weaned piglets, which can be used to develop alternative measures to antibiotics and prevent ST bacterial infection.

Identification of BoLA-DRB3.2 alleles in Korean native cattle (Hanwoo) and Holstein populations using a next generation sequencer.

Bovine leucocyte antigen (encoded by BoLA) has been widely studied to identify the association with many traits related to immunity. Exon2 of BoLA-DRB3 is extremely polymorphic, and more than 100 alleles have been identified. We investigated polymorphisms of BoLA-DRB3.2 in Korean native cattle and Holstein populations using a next generation sequencer of the GS-FLX Titanium system. We found 38 alleles including 11 new alleles (BoLA-DRB3*1303, *4702, *7101, *7501, *7201, *7301, *7601, *1104, *7701, *7401 and *50021) in Hanwoo, and nine alleles including one new allele (BoLA-DRB3*7601) in Holstein. The 454 sequencing method is a promising alternative technology for high throughput genotyping of BoLA-DRB3.2 because of its technical advantages that allow it to overcome the disadvantages of sequence-based typing methods.

Synthesis of fluorescent organic nano-dots and their application as efficient color conversion layers.

Efficient conversion of light from short wavelengths to longer wavelengths using color conversion layers (CCLs) underpins the successful operation of numerous contemporary display and lighting technologies. Inorganic quantum dots, based on CdSe or InP, for example, have received much attention in this context, however, suffer from instability and toxic cadmium or phosphine chemistry. Organic nanoparticles (NPs), though less often studied, are capable of very competitive performance, including outstanding stability and water-processability. Surfactants, which are critical in stabilizing many types of nano-structures, have not yet been used extensively in organic NPs. Here we show the utility of surfactants in the synthesis and processing of organic NPs by thoroughly characterizing the effect of ionic and non-ionic surfactants on the properties of fluorescent organic NPs. Using this information, we identify surfactant processing conditions that result in nearly 100 % conversion of organic fluorophores into sub-micrometer particles, or nano-dots, with outstanding performance as CCLs. Such water dispersions are environmentally benign and efficiently convert light. They can be used for a range of fluorophores covering a full spectral gamut, with excellent color purity, including full-width at half-maximum (FWHM) values as low as 21 nm. Compared to inorganic (InP) reference CCLs, the organic nano-dot based CCLs show superior color conversion efficiency and substantially improved long-term stability.

Erratum to: Evaluation of adenosine triphosphate testing for on-farm cleanliness monitoring compared to microbiological testing in an empty pig farrowing unit.

[This corrects the article DOI: 10.5187/jast.2020.62.5.682.].

Effect of feeding raw potato starch on the composition dynamics of the piglet intestinal microbiome.

OBJECTIVE: Raw potato starch (RPS) is resistant to digestion, escapes absorption, and is metabolized by intestinal microflora in the large intestine and acts as their energy source. In this study, we compared the effect of different concentrations of RPS on the intestinal bacterial community of weaned piglets. METHODS: Male weaned piglets (25-days-old, 7.03±0.49 kg) were either fed a corn/soybean-based control diet (CON, n = 6) or two treatment diets supplemented with 5% RPS (RPS5, n = 4) or 10% RPS (RPS10, n = 4) for 20 days and their fecal samples were collected. The day 0 and 20 samples were analyzed using a 16S rRNA gene sequencing technology, followed by total genomic DNA extraction, library construction, and high-throughput sequencing. After statistical analysis, five phyla and 45 genera accounting for over 0.5% of the reads in any of the three groups were further analyzed. Furthermore, short-chain fatty acids (SCFAs) in the day 20 fecal samples were analyzed using gas chromatography. RESULTS: Significant changes were not observed in the bacterial composition at the phylum level even after 20 d post feeding (dpf); however, the abundance of Intestinimonas and Barnesiella decreased in both RPS treatment groups compared to the CON group. Consumption of 5% RPS increased the abundance of Roseburia (p<0.05) and decreased the abundance of Clostridium (p<0.01) and Mediterraneibacter (p< 0.05). In contrast, consumption of 10% RPS increased the abundance of Olsenella (p<0.05) and decreased the abundance of Campylobacter (p<0.05), Kineothrix (p<0.05), Paraprevotella (p<0.05), and Vallitalea (p<0.05). Additionally, acetate (p<0.01), butyrate (p<0.05), valerate (p = 0.01), and total SCFAs (p = 0.01) were upregulated in the RPS5 treatment group. CONCLUSION: Feeding 5% RPS altered bacterial community composition and promoted gut health in weaned piglets. Thus, resistant starch as a feed additive may prevent diarrhea in piglets during weaning.

Johne's disease in two Korean black goats (Capra hircus coreanae) with clinical and subclinical infection: A case report.

Johne's disease (JD) is a chronic enteric infection in ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). JD infection is more difficult to diagnose in goats than cattle because MAP can insidiously affect small ruminants. Few reports have used pathological and molecular diagnosis for cases in Korean black goats. Here, we present our results from two MAP-infected goats. Case 1 was categorized as clinically significant (stage IV), with severe clinical signs and a high antibody titer (S/P ratio, 158.9%). Case 2 was in the subclinical stage (stage II); however, the goat suddenly died without any clinical signs (S/P ratio, 70.9%). DNA from the organ tissues and feces from Case 1 showed a strong positive PCR result for MAP, whereas Case 2 only exhibited a very weak reaction in the fecal sample. Moreover, fecal DNA from both cases was genotyped as C-type MAP using the PCR-REA method. Gastrointestinal organ tissues (jejunum, ileum, colon, and mesenteric lymph nodes) from Case 1 showed moderate-to-severe lesions, and acid-fast bacilli were observed. In contrast, Case 2 showed intact-to-mild pathological lesions, and acid-fast bacilli were detected in the colon, mesenteric lymph nodes, and liver. In addition, Case 2 was co-infected with Corynebacterium pseudotuberculosis, which caused caseous lymphadenitis. This case study provides valuable information regarding the pathological and molecular characteristics of JD-infected Korean black goats. The results highlighted the differences in pathological lesions between clinically and subclinically infected goats, which help veterinarians to develop better strategies to control MAP in goat farms.

Acceptor-Donor-Acceptor-Type Orange-Red Thermally Activated Delayed Fluorescence Materials Realizing External Quantum Efficiency Over 30% with Low Efficiency Roll-Off.

Two new orange-red thermally activated delayed fluorescence (TADF) materials, PzTDBA and PzDBA, are reported. These materials are designed based on the acceptor-donor-acceptor (A-D-A) configuration, containing rigid boron acceptors and dihydrophenazine donor moieties. These materials exhibit a small ΔEST of 0.05-0.06 eV, photoluminescence quantum yield (PLQY) as high as near unity, and short delayed exciton lifetime (τd ) of less than 2.63 µs in 5 wt% doped film. Further, these materials show a high reverse intersystem crossing rate (krisc ) on the order of 106 s-1 . The TADF devices fabricated with 5 wt% PzTDBA and PzDBA as emitting dopants show maximum EQE of 30.3% and 21.8% with extremely low roll-off of 3.6% and 3.2% at 1000 cd m-2 and electroluminescence (EL) maxima at 576 nm and 595 nm, respectively. The low roll-off character of these materials is analyzed by using a roll-off model and the exciton annihilation quenching rates are found to be suppressed by the fast krisc and short delayed exciton lifetime. These devices show operating device lifetimes (LT50 ) of 159 and 193 h at 1000 cd m-2 for PzTDBA and PzDBA, respectively. The high efficiency and low roll-off of these materials are attributed to the good electronic properties originatng from the A-D-A molecular configuration.

A New BODIPY Material for Pure Color and Long Lifetime Red Hyperfluorescence Organic Light-Emitting Diode.

A red fluorescent material, 1,3,7,9-tetrakis(4-(tert-butyl)phenyl)-5,5-difluoro-10-(2-methoxyphenyl)-5H-4l4,5l4-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazaborinine (4tBuMB), as an emitting dopant in a thermally activated delayed fluorescence (TADF) sensitized hyperfluorescence organic light-emitting diode (HFOLED) is reported. The 4tBuMB shows a high photoluminescence quantum yield (PLQY) of 99% with an emission maximum at 620 nm and a full width at half-maximum (fwhm) of 31 nm in solution. Further, it shows a deep lowest unoccupied molecular orbital (LUMO) of 3.83 eV. Thus, two TADF materials, 4CzIPN and 4CzTPN, as sensitizing hosts, are selected on the basis of a suitable LUMO level and spectrum overlap with 4tBuMB. The fabricated HFOLED device with 4CzTPN as a sensitizing host and 4tBuMB as an emitting dopant shows a maximum external quantum efficiency (EQE), an emission maximum, an fwhm, and CIE coordinates of 19.4%, 617 nm, 44 nm, and (0.64, 0.36), respectively. The electroluminance performances of the 4CzTPN sensitized device are higher than those of the 4CzIPN-based device, which is attributed to a higher Förster resonance energy transfer (FRET) rate and reduced intersystem crossing/reverse intersystem crossing (ISC/RISC) cycles of the former. Also, the 4CzTPN-based HF device shows a longer device lifetime (LT90) of 954 h than the 4CzIPN-baed device (LT90 of 57 h) at 3000 cd m-2. The higher device stability is due to the higher bond dissociation energies (BDEs) of 4CzTPN and 4tBuMB than that of 4CzIPN.

Comparative Analysis between Short Stem and Conventional Femoral Stem in Patients with Osteonecrosis of Femoral Head: Metha Stem and Excia Stem.

OBJECTIVE: To compare the intraoperative, radiological, and clinical short-term outcomes of cementless total hip arthroplasties (THA) using a short stem (SS) and a conventional femoral stem (CS) in a randomized prospective control study. METHODS: From June 2011 to October 2017, patients who underwent cementless THA for idiopathic osteonecrosis of the femoral head were recruited. Patients had a minimum 2 years of follow-up after the operation. The patients were divided into two groups: those who underwent THA using an SS and those who underwent THA using a CS. SS were used in 34 patients (41 hips) and CS were used in 41 patients (45 hips). In both groups, the same cup was used in all cases, and the mean follow-up periods were 63 (26-101) months in the SS and 64 (26-101) months in the CS groups. Intraoperative, clinical, and radiological evaluations were performed for the two groups. RESULTS: There was no difference in the demographics of the two groups. There was one patient with a proximal femoral crack in the SS group and one with a distal femoral crack in the CS group. Clinically, the mean Harris hip score was improved in both groups at 2-year follow-up. Radiographically endosteal osseointegrations were found in 40 of 41 cases in the SS group and in 44 of 45 cases in the CS group. There was one case of dislocation in each group. In the SS group, the acetabular cup was changed and repositioned 7 months after the initial operation. Stem loosening, infection, ceramic breakage, and varus/valgus change were not observed. There was a statistically significant lower stress shielding effect in the SS group. There were no differences in vertical/parallel offset and leg length discrepancy. CONCLUSION: The intraoperative, radiological, and clinical evaluations in both groups showed good outcomes and there was no statistically significant difference between the two groups.