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Figure-eight-shaped nonplanar π-systems adopt distinctive chiral D -symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.e., dibenzo[ 2 -symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.e., dibenzo[ g ]chrysene (DBC), catalytically affords a figure-eight electron-accepting macrocycle, i.e., cyclobisbiphenylenecarbonyl (CBBC), with high scalability (up to 3.3 g) and excellent enantioselectivity (94% ee). This inner-bond-cleavage approach also applies to larger PAHs, affording highly distorted molecular frameworks that comprise two figure-eight subunits. Furthermore, we demonstrate that the peripheral functionalization of CBBC with carbazole afforded donor-acceptor-type emitter, which shows thermally activated delayed fluorescence and emits CPL with a p ]chrysene (DBC), catalytically affords a figure-eight electron-accepting macrocycle, i.e., cyclobisbiphenylenecarbonyl (CBBC), with high scalability (up to 3.3 g) and excellent enantioselectivity (94% ee). This inner-bond-cleavage approach also applies to larger PAHs, affording highly distorted molecular frameworks that comprise two figure-eight subunits. Furthermore, we demonstrate that the peripheral functionalization of CBBC with carbazole afforded donor-acceptor-type emitter, which shows thermally activated delayed fluorescence and emits CPL with a g value of 1.0 × 10 -2 . This g value is ten times higher than those of previously reported chiral TADF-active emitters for circularly polarized organic light-emitting diodes. These results demonstrate that oxidative inner-bond cleavage is a powerful synthetic strategy for creating innovative materials that incorporate molecules with figure-eight structures.

Ticks pose a substantial public health risk as they transmit various pathogens. This concern is related to the adept blood-sucking strategy of ticks, underscored by the action of the anticoagulant, madanin, which is known to exhibit an approximately 1000-fold increase in anticoagulant activity following sulfation of its two tyrosine residues, Tyr51 and Tyr54. Despite this knowledge, the molecular mechanism underlying sulfation by tick tyrosylprotein sulfotransferase (TPST) remains unclear. In this study, we successfully prepared tick TPST as a soluble recombinant enzyme. We clarified the method by which this enzyme proficiently sulfates tyrosine residues in madanin. Biochemical analysis using a substrate peptide based on madanin and tick TPST, along with the analysis of the crystal structure of the complex and docking simulations, revealed a sequential sulfation process. Initial sulfation at the Tyr51 site augments binding, thereby facilitating efficient sulfation at Tyr54. Beyond direct biochemical implications, these findings considerably improve our understanding of tick blood-sucking strategies. Furthermore, combined with the utility of modified tick TPST, our findings may lead to the development of novel anticoagulants, promising avenues for thrombotic disease intervention and advancements in the field of public health., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Thiahexaphyrinone 1 and thia-dipyrrin-appended corrorin 2 have been synthesized. Surprisingly, further oxidation of compound 2 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dichloromethane afforded dimer 3 with two molecules of compound 2 linked at the α-carbon atoms of the thienyl units. Treatment of compound 3 with DDQ in MeOH and SnCl 2 in tetrahydrofuran/H 2 O afforded the dimethoxy-attached dimer 4 and hydrogenated dihydroxy-attached dimer 5 , respectively. These results provide the first examples for synthesizing thiophene-linked porphyrinoid dimers with tunable near-infrared absorption and chirality.

Background: Recent advances have been achieved in the genetic diagnosis and therapies against malignancies due to a better understanding of the molecular mechanisms underlying carcinogenesis. Since active preventive methods are currently insufficient, the further development of appropriate preventive strategies is desired., Methods: We searched for drinks that reactivate the functions of tumor-suppressor retinoblastoma gene (RB) products and exert anti-inflammatory and antioxidant effects. We also examined whether lactic acid bacteria increased the production of the cancer-specific anti-tumor cytokine, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), in human, and examined whether the RB-reactivating drinks with lactic acid bacteria decreased azoxymethane-induced rat colon aberrant crypt foci (ACF) and aberrant crypts (ACs) in vivo., Results: Kakadu plum juice and pomegranate juice reactivated RB functions, which inhibited the growth of human colon cancer LIM1215 cells by G1 phase arrest. These juices also exerted anti-inflammatory and antioxidant effects. Lactiplantibacillus (L.) pentosus S-PT84 was administered to human volunteers and increased the production of TRAIL. In an in vivo study, Kakadu plum juice with or without pomegranate juice and S-PT84 significantly decreased azoxymethane-induced rat colon ACF and ACs., Conclusions: RB is one of the most important molecules suppressing carcinogenesis, and to the best of our knowledge, this is the first study to demonstrate that natural drinks reactivated the functions of RB. As expected, Kakadu plum juice and pomegranate juice suppressed the growth of LIM1215 cells by reactivating the functions of RB, and Kakadu plum juice with or without pomegranate juice and S-PT84 inhibited rat colon ACF and ACs. Therefore, this mixed juice has potential as a novel candidate for cancer prevention.

Colorectal cancer is a significant cause of morbidity and represents a serious public health issue in many countries. The development of a breakthrough preventive method for colorectal cancer is urgently needed. Aspirin has recently been attracting attention as a cancer preventive drug, and its inhibitory effects on the development of various cancers have been reported in several large prospective studies. However, the underlying molecular mechanisms have not yet been elucidated in detail. In the present study, we attempted to identify the target proteins of aspirin using a chemical biology technique with salicylic acid, the main metabolite of aspirin. We generated salicylic acid-presenting FG beads and purified salicylic acid-binding proteins from human colorectal cancer HT-29 cells. The results obtained showed the potential of ribosomal protein S3 (RPS3) as one of the target proteins of salicylic acid. The depletion of RPS3 by siRNA reduced CDK4 expression and induced G1 phase arrest in human colorectal cancer cells. These results were consistent with the effects induced by the treatment with sodium salicylate, suggesting that salicylic acid negatively regulates the function of RPS3. Collectively, the present results show the potential of RPS3 as a novel target for salicylic acid in the protective effects of aspirin against colorectal cancer, thereby supporting RPS3 as a target molecule for cancer prevention., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Toshiyuki Sakai reports financial support was provided by Japan Society for the Promotion of Science., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Chronic lung disease (CLD) is a major neonatal pulmonary disorder associated with inflammation. Recent studies have shown that protein C anticoagulant pathways, such as those for protein C (PC), protein S (PS), and thrombomodulin (TM), could be useful indices for reflecting pulmonary injury. However, the involvement of these factors in preterm infants with very low birthweight (VLBW) who have developed CLD remains to be investigated. Here, we investigated whether PC pathway-related factors could predict the development of CLD in preterm infants with VLBW., Methods: We collected plasma samples from 26 preterm infants with VLBW (13 each from those with and without CLD) at the time of birth and measured TM, PC, and PS levels in their plasmas. We analyzed prospectively the relationship between these factors in infants with and without CLD., Results: There were significant differences in gestational age, birthweight, Apgar score (5 min), and duration of mechanical ventilation between the CLD and non-CLD groups. No significant differences in the PC and PS levels at birth were observed between the two groups, whereas the TM levels in the CLD group were significantly higher than those in the non-CLD group (P = 0.013). The TM levels correlated with gestational age and duration of mechanical ventilation. However, covariance analysis demonstrated that gestational age was significantly associated with TM levels, and consequently, development of CLD was not associated with TM level at birth., Conclusions: Thrombomodulin, PC, and PS levels at birth could not predict the development of CLD in preterm infants with VLBW., (© 2022 Japan Pediatric Society.)

In the 2019-2020 Australian bushfires, Kangaroo Island, South Australia, experienced catastrophic bushfires that burnt approximately half the island, with an estimated 80% of the koala population lost. During and after the event, rescued koalas were triaged at a designated facility and a range of initial data were recorded including rescue location and date, sex, estimation of age, body condition and hydration, and assessment of burn severity ( n = 304 records available). Koalas were presented to the triage facility over a span of 10 weeks, with 50.2% during the first 14 days of the bushfire response, the majority of which were rescued from regions of lower fire severity. Burns were observed in 67.4% of koalas, with the majority (60.9%) classified as superficial burns, primarily affecting the limbs and face. Poor body condition was recorded in 74.6% of burnt koalas and dehydration in 77.1%. Negative final outcomes (death or euthanasia, at triage or at a later date) occurred in 45.6% of koalas and were significantly associated with higher mean burn score, maximum burn severity, number of body regions burnt, poor body condition score, and dehydration severity. The findings of this retrospective study may assist clinicians in the field with decision making when triaging koalas in future fire rescue efforts.

Various molecular-targeting drugs have markedly improved the treatment of patients with breast cancer. As yet, therapies for triple-negative breast cancer are mainly cytotoxic agents. To investigate the novel therapy for triple-negative breast cancer, we herein examined the effects of a new combination therapy comprising a RAF/MEK inhibitor CH5126766, also known as VS-6766, which we originally discovered, and eribulin. The combination of CH5126766 and eribulin potently inhibited cell growth in the triple-negative breast cancer cell lines tested. The underlying mechanism in the efficacy of this combination treatment in vitro and in vivo was due to enhanced apoptosis through the suppression of survivin and Bcl-2 family proteins. We also showed the suppressed expression of programmed cell death ligand 1 (PD-L1) in combination therapy in vivo. We found that combination therapy with eribulin and CH5126766 for triple-negative breast cancer inhibited cell growth by apoptosis and raised a possibility that immune responses through suppression of PD-L1 might partially contribute to inhibition of tumor growth, indicating the potential of this combination as a novel strategy for triple-negative breast cancer., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Fibrillins (FBNs) form mesh-like structures of microfibrils in various elastic tissues. RECK and FBN1 are co-expressed in many human tissues, suggesting a functional relationship. We found that dermal FBN1 fibers show atypical morphology in mice with reduced RECK expression (RECK-Hypo mice). Dermal FBN1 fibers in mice-lacking membrane-type 1-matrix metalloproteinase (MT1-MMP) show a similar atypical morphology, despite the current notion that MT1-MMP (a membrane-bound protease) and RECK (a membrane-bound protease inhibitor) have opposing functions. Our experiments using dermal fibroblasts indicated that RECK promotes pro-MT1-MMP activation, increases cell-associated gelatinase/collagenase activity, and decreases diffusible gelatinase/collagenase activity, while MT1-MMP stabilizes RECK in these cells. Experiments using purified proteins indicate that RECK and its binding partner ADAMTS10 keep the proteolytic activity of MT1-MMP within a certain range. These findings suggest that RECK, ADAMTS10, and MT1-MMP cooperate to support the formation of robust FBN1 fibers., (© 2020 The Authors. Journal of Cellular Physiology published by Wiley Periodicals LLC.)

Specific monovalent cation effects on the domain-domain interaction of heterogeneous dimeric protein were investigated using green fluorescent protein (GFP)-glutathione-s-transferase (GST) fusion protein as a model protein. Conjugating N-terminal of GST domain with a fluorescence probe Cyanine3, complementary increase and decrease of fluorescence intensities of Cyanine3 and GFP were recognized on the exclusive excitation of GFP and further the fluorescence decay of GFP was remarkably accelerated to show that an excellent Förster type of resonance excitation energy transfer (FRET) pair was constructed between GFP- and GST-domain. The spectral overlap integral and critical distance of the FRET pair were estimated to be 5.96×10 13 M -1 cm 3 and 62.5 Å, respectively. The FRET rate and efficiency evaluated by fluorescence lifetime of the energy donor, GFP, were influenced by the monovalent cations included in the buffer solution to suggest that the domain-domain interactions of GFP-GST fusion protein would be susceptible to cation species and their concentrations. The order affecting the domain-domain interaction was estimated to be Li + >NH 4 + >Na + >K + >Cs + , almost corresponding to the reverse Hofmeister series.

Squamous cell lung carcinoma (SQCLC) is an aggressive type of lung cancer. In contrast with the marked advances that have been achieved in the treatment of lung adenocarcinoma, there are currently no effective targeted therapies for SQCLC, for with cytotoxic drugs are still the main treatment strategy. Therefore, the present study aimed to develop novel combination therapies for SQCLC. The results demonstrated that a combined treatment with the potent histone deacetylase (HDAC) inhibitor OBP‑801 and the third‑generation anthracycline amrubicin synergistically inhibited the viability of SQCLC cell lines by inducing apoptosis signal‑regulating kinase 1 (ASK1)‑dependent, as well as JNK‑ and p38 mitogen‑activated protein kinase (MAPK)‑independent apoptosis. OBP‑801 treatment strongly induced the protein expression levels of thioredoxin‑interacting protein (TXNIP), and amrubicin treatment increased the levels of intracellular reactive oxygen species (ROS), which suggested that this combination oxidized and dissociated thioredoxin 2 (Trx2) from mitochondrial ASK1 and activated ASK1. Moreover, mouse xenograft experiments using human H520 SQCLC cells revealed that the co‑treatment potently suppressed tumor growth in vivo. These results suggested that a combined treatment with OBP‑801 and amrubicin may have potential as a therapeutic strategy for SQCLC.

Chlamydia pecorum is an established and prevalent infection that produces severe clinical disease in many koala populations, contributing to dramatic population declines. In wild South Australian koala populations, C. pecorum occurrence and distribution is unknown. Here, C. pecorum-specific real-time quantitative PCR (qPCR) was applied to ocular and urogenital swabs from targeted surveys of wild koalas from the mainland Mount Lofty Ranges (MLR) (n = 75) and Kangaroo Island (KI) (n = 170) populations. Historical data from 13,081 KI koalas (1997-2018) provided additional evidence for assessing the absence of C. pecorum infection. In the MLR population, 46.7% (CI: 35.1-58.6%) of koalas were C. pecorum positive by qPCR but only 4% had grade 3 clinical disease. MLR koala fertility was significantly reduced by C. pecorum infection; all reproductively active females (n = 16) were C. pecorum negative, whereas 85.2% of inactive females (n = 23) were positive (P < 0.001). KI koalas were C. pecorum negative and the population was demonstrated to be free of C. pecorum infection with 95% confidence. C. pecorum is a real threat for the sustainability of the koala and KI is possibly the last isolated, large C. pecorum-free population remaining in Australia. These koalas could provide a safeguard against this serious disease threat to an iconic Australian species.

It is reasonable to consider that Type I-ribosomal inactivation proteins (RIP) retain some specific affinity to harmful pathogens to complete the role as a bio-defense relating protein. In the present studies, it was shown that two Type I-RIPs, α- and β-momorcharins, maintained the abilities to bind with N-acetylglucosamine (NAG) to change the conformation around the active sites and to regulate their N-glycosidase activities. By the binding of NAG, the freedom of internal motion of Trp192 in α-momorcharin was increased 1.5 times near the active site and, on the other hand, the corresponding motion of Trp190 was limited 50% in β-momorcharin. The results in the fluorescence resonance excitation energy transfer experiments demonstrated that Trp-190 of β-momorcharin was kept away from Tyr-70 but Trp192 contrarily approached closer to the nearest neighboring Tyr residue consisting of the active center of α-momorcharin by the binding with NAG. These conformational changes near the active site close correlated with promotion and/or suppression of the N-glucosidase activities of β- and α-momorcharins.

The tumor suppressor protein RECK has been implicated in the regulation of matrix metalloproteinases (MMPs), NOTCH-signaling and WNT7-signaling. It remains unclear, however, how broad the spectrum of RECK targets extends. To find novel RECK binding partners, we took the unbiased approach of yeast two-hybrid screening. This approach detected ADAMTS10 as a RECK-interactor. ADAMTS10 has been characterized as a metalloproteinase involved in fibrillin-rich microfibril biogenesis, and its mutations have been implicated in the connective tissue disorder Weill-Marchesani syndrome. Experiments in vitro using recombinant proteins expressed in mammalian cells indicated that RECK indeed binds ADAMTS10 directly, that RECK protects ADAMTS10 from fragmentation following chemical activation and that ADAMTS10 interferes with the activity of RECK to inhibit MT1-MMP. In cultured cells, RECK increases the amount of ADAMTS10 associated with the cells. Hence, the present study has uncovered novel interactions between two molecules of known clinical importance, RECK and ADAMTS10.This article has an associated First Person interview with the first author of the paper., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2018. Published by The Company of Biologists Ltd.)

Purpose: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. Eribulin was approved for the treatment of metastatic breast cancer through the EMBRACE trial, and a subgroup analysis in this clinical trial indicated the efficacy of eribulin in patients with TNBC. However, the prognosis of patients with TNBC is still poor due to various molecular characteristics. Therefore, there is an urgent need for a more effective treatment for the management of TNBC., Methods: We investigated the synergistic effect of a novel histone deacetylase (HDAC) inhibitor, OBP-801, and eribulin in TNBC cell lines because OBP-801 has been known to enhance the anti-tumor activities of other chemotherapeutic agents. The cell growth was analyzed, and the flow cytometry analysis was conducted to evaluate the effects on cell cycle and the induction of apoptosis. The mechanism underlying the enhancement of inhibition of TNBC cell growth was investigated through Western blot analyses., Results: The combination treatment of OBP-801 with eribulin showed the synergistic inhibition of the growth in TNBC cells, involved with the enhancement of apoptosis. We, for the first time, found that eribulin upregulated survivin and also that OBP-801 could remarkably suppress the upregulation of survivin by eribulin. Moreover, this combination potently suppressed Bcl-xL and the MAPK pathway compared with either agent alone., Conclusion: We found that the combination of OBP-801 and eribulin synergistically inhibited the growth with apoptosis in TNBC cells, suggesting that this combination might be a promising novel strategy for treating TNBC patients.

The peripheral auditory nerve (AN) carries sound information from sensory hair cells to the brain. The present study investigated the contribution of mouse and human hematopoietic stem cells (HSCs) to cellular diversity in the AN following the destruction of neuron cell bodies, also known as spiral ganglion neurons (SGNs). Exposure of the adult mouse cochlea to ouabain selectively killed type I SGNs and disrupted the blood-labyrinth barrier. This procedure also resulted in the upregulation of genes associated with hematopoietic cell homing and differentiation, and provided an environment conducive to the tissue engraftment of circulating stem/progenitor cells into the AN. Experiments were performed using both a mouse-mouse bone marrow transplantation model and a severely immune-incompetent mouse model transplanted with human CD34 + cord blood cells. Quantitative immunohistochemical analysis of recipient mice demonstrated that ouabain injury promoted an increase in the number of both HSC-derived macrophages and HSC-derived nonmacrophages in the AN. Although rare, a few HSC-derived cells in the injured AN exhibited glial-like qualities. These results suggest that human hematopoietic cells participate in remodeling of the AN after neuron cell body loss and that hematopoietic cells can be an important resource for promoting AN repair/regeneration in the adult inner ear.

Dihydrolipoamide dehydrogenase (LipDH) transfers two electrons from dihydrolipoamide (DHL) to NAD(+) mediated by FAD. Since this reaction is the final step of a series of catalytic reaction of pyruvate dehydrogenase multi-enzyme complex (PDC), LipDH is a key enzyme to maintain the fluent metabolic flow. We reported here the conformational change near the redox center of LipDH induced by NAD(+) promoting the access of the DHL to FAD. The increase in the affinity of DHL to redox center was evidenced by the decrease in K M responding to the increase in the concentration of NAD(+) in Lineweaver-Burk plots. The fluorescence intensity of FAD transiently reduced by the addition of DHL was not recovered but rather reduced by the binding of NAD(+) with LipDH. The fluorescence decay lifetimes of FAD and Trp were prolonged in the presence of NAD(+) to show that FAD would be free from the electron transfer from the neighboring Tyrs and the resonance energy transfer efficiency between Trp and FAD lowered. These results consistently reveal that the conformation near the FAD and the surroundings would be so rearranged by NAD(+) to allow the easier access of DHL to the redox center of LipDH.

Aim: The present study was carried out to clarify tube feeding utilization and the prevalence of swallowing difficulty among residents in geriatric long-term settings, and to elucidate the implementation of swallowing assessment at four different types of facilities in Japan., Methods: We mailed a questionnaire to a total of 4334 facilities., Results: We received responses from 1137 (26.2%) facilities, including 440 (29.0%) from 1517 nursing homes, 275 (29.2%) from 941 long-term care facilities, 205 (18.1%) from 1134 sanatorium medical facilities and 217 (29.2%) from 742 rehabilitation hospitals. The number of tube-fed residents per 100 beds in each facility was 11.6 at the nursing homes, 7.4 at the long-term care facilities, 36.3 at the sanatorium medical facilities and 7.9 at the rehabilitation facilities. The number of residents per 100 beds with swallowing difficulty was 23.7 in the nursing homes, 15.6 in the long-term care facilities, 19.2 in the sanatorium medical facilities and 15.4 in the rehabilitation hospitals. The percentages of facilities that assessed swallowing difficulty were 31.8% of the nursing homes, 63.0% of the long-term care facilities, 77.9% of the sanatorium medical facilities and 91.7% of the rehabilitation hospitals., Conclusion: A large number of residents using a feeding tube and with difficult swallowing were observed in geriatric long-term settings without adequate evaluation of swallowing function., (© 2013 Japan Geriatrics Society.)

In various trials for elucidating the physiological function of pokeweed antiviral protein (PAP), studies on the interaction with sugar are essential. The fluorescence titration curves showed that PAP retained the strong affinity against N-acetylglucosamine (NAG) and two sites in one PAP molecule co-operatively participated in the binding. In the complex of PAP with NAG, Trp208 located at the entrance lid site of substrate came closer to Tyr72 about 0.3 Å. Furthermore, the fluorescence anisotropy decay measurement demonstrated that the segmental rotation of Trp208 was enlarged by the binding of PAP with NAG. Such conformational changes around the active site closely correlate with the enzymatic activity of PAP. The N-glycosidase activity of PAP was enhanced more than two times in the presence of NAG. The obtained results consistently suggested the enzymatic activity of PAP would be regulated through the conformation change near the active site induced by the binding with NAG.

Ribonuclease P (RNase P) is a ribonucleoprotein complex essential for the processing of 5' leader sequences of precursor tRNAs (pre-tRNA). PhoPop5 is an archaeal homolog of human RNase P protein hPop5 involved in the activation of RNase P RNA (PhopRNA) in the hyperthermophilic archaeon Pyrococcus horikoshii, probably by promoting RNA annealing (AN) and RNA strand displacement (SD). Although PhoPop5 folds into the RNA recognition motif (RRM), it is distinct from the typical RRM in that it has an insertion of α-helix (α2) between α1 and β2. Biochemical and structural data have shown that the dimerization of PhoPop5 through the loop between α1 and α2 is required for the activation of PhopRNA. In addition, PhoPop5 has additional helices (α4 and α5) at the C-terminus, which pack against one face of the β-sheet. In this study, we examined the contribution of the C-terminal helices to the activation of PhopRNA using mutation analyses. Reconstitution experiments and fluorescence resonance energy transfer (FRET)-based assays indicated that deletion of the C-terminal helices α4 and α5 significantly influenced on the pre-tRNA cleavage activity and abolished AN and SD activities, while that of α5 had little effect on these activities. Moreover, the FRET assay showed that deletion of the loop between α1 and α2 had no influence on the AN and SD activity. Further mutational analyses suggested that basic residues at α4 are involved in interaction with PhopRNA, while hydrophobic residues at α4 participate in interaction with hydrophobic residues at the β-sheet, thereby stabilizing an appropriate orientation of the helix α4. Together, these results indicate that extra-structural elements in the RRM in PhoPop5 play a crucial role in the activation of PhopRNA., (Copyright © 2013 Elsevier Inc. All rights reserved.)