Mechanochemical Synthesis of Perovskite Oxyhydrides: Insights from Shear Modulus.

Perovskite oxyhydrides have attracted recent attention due to their intriguing properties such as ionic conductivity and catalysis, but their repertoire is still restricted compared to perovskite oxynitrides and oxyfluorides. Historically, perovskite oxyhydrides have been prepared mostly by topochemical reactions and high-pressure (HP) reactions, while in this study, we employed a mechanochemical (MC) approach, which enables the synthesis of a series of ABO2H-type oxyhydrides, including those with the tolerance factor (t) much smaller than 1 (e.g., SrScO2H with t = 0.936) which cannot be obtained by HP synthesis. The octahedral tilting, often present in perovskite oxides, does not occur, suggesting that the lack of π-symmetry of the H 1s orbital and the large polarization destabilize tilted low-symmetry structures. Interestingly, SrCrO2H (t = 0.997), previously reported with the HP method, was not achieved with the MC method. A comparative analysis revealed a correlation between the feasibility of MC reactions and the (calculated) shear modulus of the starting reagents (binary oxides and hydrides). Notably, this indicator is not exclusive to oxyhydride perovskites but extends to oxide perovskites (SrMO3). This study demonstrates that MC synthesis offers unique opportunities not only to expand the compositional space in oxyhydrides in various structural types but also to provide a guide for the choice of starting materials for the synthesis of other compounds.

State-dependent inhibition of GABA receptor channels by the ectoparasiticide fluralaner.

γ-Aminobutyric acid (GABA) receptors (GABARs) are ligand-gated Cl- channels, which cause an influx of Cl- that inhibits excitation in postsynaptic cells upon activation. GABARs are important targets for drugs and pest control chemicals. We previously reported that the isoxazoline ectoparasiticide fluralaner inhibits GABA-induced currents in housefly (Musca domestica) GABARs by binding to the putative binding site in the transmembrane subunit interface. In the present study, we investigated whether fluralaner inhibits the GABA response in the GABAR activated state, the resting state, or both, using two-electrode voltage clamp electrophysiology protocols. We found that inhibition progresses over time to steady-state levels by repeated short applications of GABA during fluralaner perfusion. The GABA response was not impaired by fluralaner treatment in the GABAR resting state. However, once inhibited, the GABA response was not restored by repeated applications of GABA. These findings suggest that fluralaner might reach the binding site of the activated conformation of GABARs in a stepwise fashion and tightly bind to it.

Effects of intersubunit amino acid substitutions on GABA receptor sensitivity to the ectoparasiticide fluralaner.

The isoxazoline ectoparasiticide fluralaner exerts antiparasitic effects by inhibiting the function of γ-aminobutyric acid (GABA) receptors (GABARs). The present study was conducted to identify the amino acid residues that contribute to the high sensitivity of insect GABARs to fluralaner. We generated housefly (Musca domestica) GABARs with amino acid substitutions in the first through third α-helical transmembrane segments (TM1-TM3) of the RDL subunit using site-directed mutagenesis and examined the effects of the substitutions on the sensitivity of GABARs expressed in Xenopus oocytes to fluralaner using two-electrode voltage clamp electrophysiology. The Q271L substitution in TM1 caused a significant reduction in the sensitivity to fluralaner. Although the I274A and I274F substitutions in TM1 did not affect fluralaner sensitivity, the I274C substitution significantly enhanced the sensitivity to fluralaner. In contrast, the L278C substitution in TM1 reduced fluralaner sensitivity. Substitutions of Gly333 in TM3 led to substantial reductions in the sensitivity to fluralaner. These findings indicate that Gln271, Ile274, Leu278, and Gly333, which are situated in the outer half of the transmembrane subunit interface, are closely related to the antagonism of GABARs by fluralaner.

Influence of hyperbaric oxygen therapy on thrombus formation ability in humans.

Background: Hyperbaric oxygen (HBO2) therapy was introduced nearly 300 years ago. However, its effect on thrombus formation is unclear. This may be because platelet and coagulation functions are unstable, yielding variable results; hence, accurate measurement is difficult. Our study aimed to analyze changes in thrombus formation before and after HBO2 therapy by using a total thrombus formation analysis system (TTAS). Methods: Six patients were prescribed HBO2 therapy for skin and soft tissue ulcers, and necrotic fasciitis. Blood samples were collected immediately before and after treatment. Then samples were put into a reservoir that connected to AR-chip to assess changes in the thrombus formation ability of both platelets and coagulation factors. We examined the differences in the thrombus formation ability using T-TAS. Time until the onset of white thrombus formation (T10) and complete occlusion of the capillary (T80) were analyzed by a two-way repeated measure analysis of variance (ANOVA). Results: The duration to pressure increase of samples after HBO2 therapy was longer than the duration before HBO2 therapy (p<0.05). This suggests decreased clot adhesiveness to the inner surface of the simulated blood vessel and reduced clot formation ability. Conclusions: The results for T10 and T80 suggest that HBO2 therapy reduced thrombus formation ability in the enrolled patients. We believe that T-TAS is a promising method to predict the efficacy of HBO2 therapy.

[Actual state of injection techniques and effect of medical treatment instructions in elderly patients with diabetes using insulin].

AIM: Support for elderly patients using insulin to continue self-injection safely is required for clinical settings. The aim of this study was 1) to clarify the actual state of self-injection procedures for elderly people injecting insulin and 2) to verify whether or not the injection procedures can be improved by nurses' medical treatment instructions. SUBJECTS AND METHODS: The subjects were outpatients at an educational facility certified by the Japan Diabetes Society. Basic clinical characteristics, the Mini-Cog cognitive function test, basic ADL and instrumental ADL, and 24 items of the self-injection procedure were evaluated by nurses. After receiving a 30-minute face-to-face session of individual instructions from trained nurses two or more times, the injection procedure was re-evaluated. RESULTS: Of the 63 study subjects, 10 were injecting insulin with the support of others (supported injection group). The median age in the self-injection group was 72 years old, while that in the supported injection group was 82 years old. The supported injection group was older, the female ratio higher, and the Mini-Cog and ADL indices lower than in the self-injection group (p <0.05). The median history of the use of insulin was over 10 years in both groups. In the self-injection group, the degree of proficiency with the injection technique was significantly improved after receiving the instructions (p <0.05). The biggest improvement was in response to the question, "Do you know that you need to shift the site of injections?", which doubled (p <0.05). The correct answer rate for "Do you know the name of your insulin formulation?" was less than half, and it remained unchanged even after receiving instructions. In the supported injection group, 90% had a Mini-Cog of ≤2 points, but 6 subjects (60%) were able to perform an injection by themselves with others supporting the adjustments made to the amount of insulin. CONCLUSIONS: The self-injection technique improved significantly, even in elderly people, following the delivery of medical treatment instructions by nurses, and the item with the highest improvement effect was subjects' understanding of the need to shift the injection site. Our study showed that even in elderly people with cognitive dysfunction who are performing injections with the support of others, some of the injection procedures were retained by relying on procedural memory acquired in the past.

Fluxametamide: A novel isoxazoline insecticide that acts via distinctive antagonism of insect ligand-gated chloride channels.

Fluxametamide is a novel wide-spectrum insecticide that was discovered and synthesized by Nissan Chemical Industries, Ltd. To identify the mode of action of fluxametamide, we first performed [3H]4'-ethynyl-4-n-propylbicycloorthobenzoate (EBOB) binding assays. Fluxametamide potently inhibited the specific binding of [3H]EBOB to housefly-head membranes, suggesting that fluxametamide affects insect γ-aminobutyric acid (GABA)-gated chloride channels (GABACls). Next, the antagonism of housefly GABACls and glutamate-gated chloride channels (GluCls) was examined using the two-electrode voltage clamp (TEVC) method. Fluxametamide inhibited agonist responses in both ion channels expressed in Xenopus oocytes in the nanomolar range, indicating that this insecticide is a ligand-gated chloride channel (LGCC) antagonist. The insecticidal and LGCC antagonist potencies of fluxametamide against fipronil-susceptible and fipronil-resistant strains of small brown planthoppers and two-spotted spider mites, which are insensitive to fipronil, were evaluated. Fluxametamide exhibited similar levels of both activities in these fipronil-susceptible and fipronil-resistant arthropod pests. These data indicate that fluxametamide exerts distinctive antagonism of arthropod GABACls by binding to a site different from those for existing antagonists. In contrast to its profound actions on the arthropod LGCCs, the antagonistic activity of fluxametamide against rat GABACls and human glycine-gated chloride channels was nearly insignificant, suggesting that fluxametamide has high target-site selectivity for arthropods over mammals. Overall, fluxametamide is a new type of LGCC antagonist insecticide with excellent safety for mammals at the target-site level.

A Single Amino Acid Substitution in the Third Transmembrane Region Has Opposite Impacts on the Selectivity of the Parasiticides Fluralaner and Ivermectin for Ligand-Gated Chloride Channels.

Fluralaner (Bravecto) is a recently marketed isoxazoline ectoparasiticide. This compound potently inhibits GABA-gated chloride channels (GABACls) and less potently glutamate-gated chloride channels (GluCls) in insects. The mechanism underlying this selectivity is unknown. Therefore, we sought to identify the amino acid residues causing the low potency of fluralaner toward GluCls. We examined the fluralaner sensitivity of mutant housefly (Musca domestica) GluCls in which amino acid residues in the transmembrane subunit interface were replaced with the positionally equivalent amino acids of Musca GABACls. Of these amino acids, substitution of an amino acid (Leu315) in the third transmembrane region (TM3) with an aromatic amino acid dramatically enhanced the potency of fluralaner in the GluCls. In stark contrast to the enhancement of fluralaner potency, this mutation eliminated the activation of currents and the potentiation but not the antagonism of glutamate responses that are otherwise all elicited by the macrolide parasiticide ivermectin (IVM). Our findings indicate that the amino acid Leu315 in Musca GluCls plays significant roles in determining the selectivity of fluralaner and IVM for these channels. Given the high sequence similarity of TM3, this may hold true more widely for the GluCls and GABACls of other insect species.

External amino acid residues of insect GABA receptor channels dictate the action of the isoxazoline ectoparasiticide fluralaner.

BACKGROUND: Fluralaner is the first isoxazoline ectoparasiticide developed to protect companion animals from fleas and ticks. Fluralaner primarily inhibits arthropod γ-aminobutyric acid receptors (GABARs), which are ligand-gated ion channels comprising five subunits arranged around the channel pore. We previously reported that the action site of fluralaner resides at the M1-M3 transmembrane interface between adjacent GABAR subunits. To investigate whether fluralaner interacts with the second transmembrane segment (M2) located deep in the interface, we generated four housefly RDL GABAR mutants with non-conservative amino acid substitutions in the M2 region. RESULTS: Electrophysiological analysis of GABARs expressed in Xenopus oocytes indicated that S313A and S314A mutants exhibited fluralaner sensitivities similar to that of the wild type. M312S mutant exhibited approximately seven-fold lower sensitivity than that of the wild type. Notably, the N316L mutant was almost insensitive to fluralaner. CONCLUSION: The findings of this study indicate that the conserved external amino acid residues of insect GABAR channels play a critical role in the antagonistic effect of fluralaner. © 2023 Society of Chemical Industry.

Coagulation Influencing Liberation from Respiratory Support in Patients with Coronavirus Disease 2019: A Retrospective, Observational Study.

BACKGROUND: Patients with coronavirus disease 2019 (COVID-19) occasionally develop respiratory failure and coagulopathy. We aimed to determine whether coagulation abnormalities at admission and during the course of hospitalization can predict the liberation from respiratory support in critically ill patients with COVID-19 by combining the results of rotational thromboelastometry (ROTEM) with standard laboratory tests. METHODS: This single-center, retrospective, observational study included 31 consecutive adult patients with COVID-19 who were admitted to the intensive care unit (ICU) and who required respiratory support between April 2021 and August 2021. We divided the patients into two groups according to the liberation from respiratory support and analyzed the differences between the groups. RESULTS: There were 20 patients in the liberation group and 11 in the non-liberation group. There were no significant differences in the overt disseminated intravascular coagulation scores or abnormal counts in the ROTEM parameters at admission between groups, although there was a significant difference in the highest score in the ICU. The Sequential Organ Failure Assessment and sepsis-induced coagulopathy scores were significantly different between both groups at admission and at the time when the highest values were reported during the ICU stay. CONCLUSIONS: High sepsis-induced coagulopathy scores at admission to the ICU were found to be useful predictors of difficulties in the liberation from respiratory support in patients with severe COVID-19. However, increased overt disseminated intravascular coagulation scores and abnormal counts in the ROTEM parameters during the ICU stay were associated with difficulties in the liberation from respiratory support.

Investigation of predictors of bleeding complications in COVID-19 using rotational thromboelastometry (ROTEMⓇ): A retrospective study.

Background: Hemorrhagic complications in patients with coronavirus 19 disease (COVID-19) are infrequent but associated with a prognosis. This study aimed to elucidate the risk factors for bleeding complications in patients with COVID-19 using rotational thromboelastometry (ROTEM) parameters and blood tests performed at admission. Methods: In total, 31 patients with severe COVID-19 treated intensively at Saga University Hospital were included in this study. Patients were divided into two groups according to the presence or absence of hemorrhagic complications. Results from the blood tests performed at admission and during hospitalization, and ROTEM values acquired upon admission, were compared between the two groups. Results: There were significant differences in ROTEM values upon admission between the bleeding and non-bleeding groups. Receiver operating curve analysis showed that the area under the curve for prothrombin time international normalized ratio (PT-INR) and extrinsically-activated test with tissue factor (EXTEM) amplitude at 10 min (A10) were 0.82 (0.52-0.92) and 0.81 (0.58-0.93), respectively. Logistic regression analysis with PT-INR and EXTEM A10 as factors calculated an odds ratio of 1.94 (1.04-3.62) and EXTEM A10 0.86 (0.71-1.05) for bleeding complications occurrence. Conclusion: ROTEM may be a sensitive predictor for bleeding complications in patients with COVID-19.

Usefulness of a medical interview support application for residents: A pilot study.

To conduct an appropriate medical interview, education and clinical experience are necessary. The usefulness of computer-based medical diagnostic support systems has been reported in medical interviewing. However, only a few reports have actually applied these systems and noted changes in the quality of the medical interview of residents. We aimed to examine how the use of a medical interview support application changes the medical interviews of residents. The study was conducted on 15 residents (with less than two years post-graduation) and ran from November 2020 to March 2021. Faculty members played the role of simulated patients in 20 cases, and the residents conducted the medical interviews. In 10 of the 20 cases, a medical interview support application was used. After the interview, the residents were asked to list up to 10 differential diseases; the interview was considered appropriate if it included the disease portrayed by the simulated patient. Furthermore, the duration of the medical interview, the number of questions asked, and changes in stress parameters were evaluated. The use of a medical interview support application increased the percentage of appropriate medical interviews. Considering the frequency, the use of a medical interview support application increased the rate of appropriate medical interviews in the rare disease group, as well as the number of questions and duration of the interviews. No stress reduction was observed. The medical interview support application may be a useful tool in identifying appropriate differential diseases during medical interviews by residents.

Development of a delirium predictive model for adult trauma patients in an emergency and critical care center: a retrospective study.

BACKGROUND: Delirium has been shown to prolong the length of intensive care unit stay, hospitalization, and duration of ventilatory control, in addition to increasing the use of sedatives and increasing the medical costs. Although there have been a number of reports referring to risk factors for the development of delirium, no model has been developed to predict delirium in trauma patients at the time of admission. This study aimed to create a scoring system that predicts delirium in trauma patients. METHODS: In this single-center, retrospective, observational study, trauma patients aged 18 years and older requiring hospitalization more than 48 hours were included and divided into the development and validation cohorts. Univariate analysis was performed in the development cohort to identify factors significantly associated with prediction of delirium. The final scoring system for predicting delirium was developed using multivariate analysis and internal validation was performed. RESULTS: Of the 308 patients in the development cohort, 91 developed delirium. Clinical Frailty Score, fibrin/fibrinogen degradation products, low body mass index, lactate level, and Glasgow Coma Scale score were independently associated with the development of delirium. We developed a scoring system using these factors and calculated the delirium predictive score, which had an area under the curve of 0.85. In the validation cohort, 46 of 206 patients developed delirium. The area under the curve for the validation cohort was 0.86, and the calibration plot analysis revealed the scoring system was well calibrated in the validation cohort. DISCUSSION: This scoring system for predicting delirium in trauma patients consists of only five risk factors. Delirium prediction at the time of admission may be useful in clinical practice. LEVEL OF EVIDENCE: Prognostic and epidemiological, level III.

The antiparasitic isoxazoline A1443 is a potent blocker of insect ligand-gated chloride channels.

A structurally unique isoxazoline class compound, A1443, exhibits antiparasitic activity against cat fleas and dog ticks comparable to that of the commercial ectoparasiticide fipronil. This isoxazoline compound inhibits specific binding of the gamma-aminobutyric acid (GABA) receptor channel blocker [(3)H]4'-ethynyl-4-n-propylbicycloorthobenzoate (EBOB) to housefly-head membranes, with an IC(50) value of 455pM. In contrast, the IC(50) value in rat-brain membranes is>10muM. To study the mode of action of this isoxazoline, we utilized MdGBCl and MdGluCl cDNAs, which encode the subunits of housefly GABA- and glutamate-gated chloride channels, respectively. Two-electrode voltage clamp electrophysiology was used to confirm that A1443 blocks GABA- and glutamate-induced chloride currents in Xenopus oocytes expressing MdGBCl or MdGluCl channels, with IC(50) values of 5.32 and 79.9 nM, respectively. Blockade by A1443 was observed in A2'S-MdGBCl and S2'A-MdGluCl mutant channels at levels similar to those of the respective wild-types, and houseflies expressing A2'S-MdGBCl channels were as susceptible to A1443 as standard houseflies. These findings indicate that A1443 is a novel and specific blocker of insect ligand-gated chloride channels.

Glycosylation and ligand-binding activities of rat plasma fibronectin during liver regeneration after partial hepatectomy.

Fibronectin (FN) is a multifunctional glycoprotein present in the extracellular matrix (ECM) and plasma. We previously reported that the glycosylation and ligand-binding of vitronectin (VN) change markedly after partial hepatectomy (PH). Here we show the changes of FN during liver regeneration. The yields of purified sham-operated (SH-) and PH-FN were higher than that of non-operated (NO)-FN, while binding activities of FNs to ECM ligands were changed only slightly by hepatectomy. The carbohydrate concentration of PH-FN decreased to 66% of that of NO- and SH-FN. By using LC/MS(n), eight kinds of complex-type N-glycan structures were found to be present in all FNs, and bi- and trisialobiantennary glycans were the major structures. Fucosylation was markedly increased, while O-acetylation of sialic acid was found to be decreased in PH-FN. The alterations in glycosylation and biological activities of FN after PH are different from those of VN, suggesting that these glycoproteins play different biological functions in tissue remodeling.

Differential mechanisms of action of the novel γ-aminobutyric acid receptor antagonist ectoparasiticides fluralaner (A1443) and fipronil.

BACKGROUND: Fluralaner (A1443) is an isoxazoline ectoparasiticide that is a novel antagonist of γ-aminobutyric acid (GABA) receptors (GABARs), with a potency comparable to that of fipronil, a phenylpyrazole ectoparasiticide. To clarify the biological effectiveness of fluralaner against fipronil-resistant pests, differences in the actions of fluralaner and fipronil on GABARs that possess resistance to dieldrin (rdl)-type mutations were evaluated. RESULTS: Fipronil had neither pest control nor GABAR-antagonistic activities against two-spotted spider mites (Tetranychus urticae) that had two different rdl-type amino acids (A(301) → H and T(350) → A: Drosophila melanogaster GABAR numbering) and against small brown planthoppers (Laodelphax striatellus) that had a novel rdl-type (A(283) → N) mutation in GABARs. In contrast, fluralaner showed not only high pest control activities against these pests, but also excellent antagonistic activities for these rdl-type GABARs. CONCLUSION: The findings indicate that rdl-type fipronil-resistant pests do not show cross-resistance to fluralaner owing to the differential actions of fluralaner and fipronil on the GABAR.