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Abstract: Thin (∼25nm) zincblende GaN (111) epilayers have been grown on hexagonal ZrB2 (0001) substrates by plasma-assisted molecular-beam epitaxy at temperatures near 600°C. Layers grown in near-stoichiometric conditions exhibit high phase purity; no wurtzite inclusions are detected by high-resolution X-ray diffraction or photoluminescence. For growth in the presence of excess Ga the layers are predominantly zincblende phase, but contain some wurtzite inclusions. Reducing the growth temperature to 400°C results in a much-increased fraction of wurtzite inclusions. The growth of zincblende GaN with high phase purity on hexagonal ZrB2 implies the existence of an underlying physical mechanism rather than simply a result of “growth mistakes.” A possible surface energy-related mechanism by which zincblende GaN (111) can be preferentially nucleated on hexagonal substrates is discussed. [Copyright &y& Elsevier]

Glutathione (GSH) is required for various physiological processes in plants, including redox regulation and detoxification of harmful compounds. GSH also functions as a repository for assimilated sulfur and is actively catabolized in plants. In Arabidopsis, GSH is mainly degraded initially by cytosolic enzymes, γ-glutamyl cyclotransferase, and γ-glutamyl peptidase, which release cysteinylglycine (Cys-Gly). However, the subsequent enzyme responsible for catabolizing this dipeptide has not been identified to date. In the present study, we identified At4g17830 as a Cys-Gly dipeptidase, namely cysteinylglycine peptidase 1 (CGP1). CGP1 complemented the phenotype of the yeast mutant that cannot degrade Cys-Gly. The Arabidopsis cgp1 mutant had lower Cys-Gly degradation activity than the wild type and showed perturbed concentrations of thiol compounds. Recombinant CGP1 showed reasonable Cys-Gly degradation activity in vitro. Metabolomic analysis revealed that cgp1 exhibited signs of severe sulfur deficiency, such as elevated accumulation of O-acetylserine (OAS) and the decrease in sulfur-containing metabolites. Morphological changes observed in cgp1, including longer primary roots of germinating seeds, were also likely associated with sulfur starvation. Notably, At4g17830 has previously been reported to encode an N 2 -acetylornithine deacetylase (NAOD) that functions in the ornithine biosynthesis. The cgp1 mutant did not show a decrease in ornithine content, whereas the analysis of CGP1 structure did not rule out the possibility that CGP1 has Cys-Gly dipeptidase and NAOD activities. Therefore, we propose that CGP1 is a Cys-Gly dipeptidase that functions in the cytosolic GSH degradation pathway and may play dual roles in GSH and ornithine metabolism., (© 2024 Society for Experimental Biology and John Wiley & Sons Ltd.)

Conformer-selected electronic and vibrational spectra of benzyl methyl ether and its terminal methyl group-substituted derivative in a supersonic jet have been measured using ultraviolet (UV)-UV hole burning and fluorescence-detected infrared spectroscopy to investigate the conformational stability of flexible molecules. Various quantum chemical calculations as well as experimental observations reveal the coexistence of three conformers with different CCOC dihedral angles and side-chain orientations relative to the benzene ring plane. Vibrational analysis in the excited state with time-dependent density functional theory and IR simulations containing anharmonic coupling sufficiently reproduce the experimental results, suggesting that these three conformers can be distinguished into one gauche -conformer and two trans -ones with respect to the CCOC dihedral angle. We also observe that the gauche conformer exhibits higher-frequency CH 2 modes. The natural bond orbital analysis indicates that this phenomenon is attributed to the electron delocalization from the non-bonding orbitals and the C-O orbitals associated with the neighboring oxygen atom, which leads to a conformer dependence of the methylene C-H bond strength.

Glutathione (GSH) functions as a major sulfur repository and hence occupies an important position in primary sulfur metabolism. GSH degradation results in sulfur reallocation and is believed to be carried out mainly by γ-glutamyl cyclotransferases (GGCT2;1, GGCT2;2, and GGCT2;3), which, however, do not fully explain the rapid GSH turnover. Here, we discovered that γ-glutamyl peptidase 1 (GGP1) contributes to GSH degradation through a yeast complementation assay. Recombinant proteins of GGP1, as well as GGP3, showed high degradation activity of GSH, but not of oxidized glutathione (GSSG), in vitro. Notably, the GGP1 transcripts were highly abundant in rosette leaves, in agreement with the ggp1 mutants constantly accumulating more GSH regardless of nutritional conditions. Given the lower energy requirements of the GGP- than the GGCT-mediated pathway, the GGP-mediated pathway could be a more efficient route for GSH degradation than the GGCT-mediated pathway. Therefore, we propose a model wherein cytosolic GSH is degraded chiefly by GGP1 and likely also by GGP3. Another noteworthy fact is that GGPs are known to process GSH conjugates in glucosinolate and camalexin synthesis; indeed, we confirmed that the ggp1 mutant contained higher levels of O-acetyl-l-Ser, a signaling molecule for sulfur starvation, and lower levels of glucosinolates and their degradation products. The predicted structure of GGP1 further provided a rationale for this hypothesis. In conclusion, we suggest that GGP1 and possibly GGP3 play vital roles in both primary and secondary sulfur metabolism., (© 2022 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

Competing Interests: The other authors have stated explicitly that there are no conflicts of interest in connection with this article.

Background: Population aging requires more physician home visits, and various measures need to be taken to reduce the burden on visiting physicians. However, the incidence and associated factors of burdensome emergency home visits remain unclear. We aimed to reveal the incidences of emergency home visits among cancer and noncancer patients and examine how visiting nurses affect those., Methods: We performed a prospective cohort study across three clinics in Japan and enrolled the patients receiving home visits within a 3-month study period. We calculated the incidence rates using person-time at risk and conducted a Cox regression in the analysis of risks for emergency home visits., Results: A total of 278 patients were analyzed. The incidences of emergency home visits among the overall, the cancer, and the noncancer home care patients were 1.61, 7.23, and 1.37 per 10 person-months, respectively. The adjusted hazard ratios of a cancer-bearing state and visiting nurse service use were 4.71 (95% confidence interval [CI], 2.60-8.52) and 1.85 (95% CI, 1.77-1.94), respectively., Conclusions: The incidence of emergency home visits among cancer patients was around five times greater than noncancer patients. Our study did not demonstrate that visiting nurses prevent emergency home visits. Further studies are needed to clarify how visiting nurses reduce physicians' burden., Competing Interests: The authors have stated explicitly that there are no conflicts of interest in connection with this article., (© 2021 The Authors. Journal of General and Family Medicine published by John Wiley & Sons Australia, Ltd on behalf of Japan Primary Care Association.)

Group A consisted of chickens infected with a single dose of Ascaris suum and group B of chickens infected with two successive doses. At days 1, 3, 7, 14 and 21 after the first or second infection dose, six chickens from each group were sacrificed. In both groups, larvae were recovered from the livers on days 1, 3, and 7 and lungs on days 3 and 7. No larvae were detected in chickens on day 14. Clear white lesions were noticed only on the livers from chickens of group B at day 7 but had disappeared at day 14. A comparison with group B showed mild histological changes that developed relative to the livers from group A.

Serum alpha-fetoprotein (AFP) values were measured in hepatic diseased dogs with or without tumor and non-hepatic tumor bearing dogs by a sandwich ELISA using anti-dog AFP antiserum. Serum AFP values were less than 70 ng/ml in clinically healthy dogs. The values in dogs with hepatocellular carcinoma were higher than 1,400 ng/ml in 7 of 9 dogs, wherever those in two dogs with cholangiocarcinoma were in the normal range. Serum AFP values in hepatic diseased dogs without tumor were also high, however, the values were below 500 ng/ml in 90% of the dogs. In non-hepatic tumor dogs, serum AFP values were less than 500 ng/ml in 76% of the dogs. In the surgically removal cases with hepatocellular carcinoma, serum AFP values rapidly decreased. These results suggested that the sandwich ELISA using anti-dog AFP antiserum was an available method for diagnosis of hepatocellular carcinoma in dogs.

Objective: To determine the role of platelet activating factor (PAF) in lipopolysaccharide (LPS)-induced thrombocytopenia and neutropenia in dogs., Animals: 42 dogs., Procedures: Blood samples were obtained from dogs given LPS (40 microg/kg of body weight; n = 16), PAF (1 microg/kg; 6), PAF (5 microg/kg/h for 90 minutes; 4), or physiologic saline (0.9% NaCl) solution (0.1 ml/kg/h for 90 minutes; 3) IV to monitor changes in blood cell counts, using automated counters and blood smears stained with Giemsa. Blood samples were also obtained from dogs given LPS (40 microg/kg) that had (n = 5) or had not (6) been treated beforehand with TCV-309, a potent PAF antagonist. Concentration of PAF in blood was determined by use of 125I-radioimmunoassay in dogs given LPS at 1 mg/kg (n = 3) and 40 microg/kg (9)., Results: Thrombocytopenia and neutropenia were found in all dogs except those given saline solution. The LPS-induced thrombocytopenia was significantly suppressed by prior treatment with TCV-309. The PAF concentrations increased markedly 1 hour after injection of 1 mg/kg of LPS and increased slightly but significantly 10 minutes after injection of 40 microg/kg of LPS., Conclusion and Clinical Relevance: PAF plays an important role in the development of LPS-induced thrombocytopenia and neutropenia in dogs. Control of PAF production, PAF-induced effects, or both may be important in the treatment of dogs with gram-negative bacterial infections and associated thrombocytopenia and neutropenia.

Canine alpha-fetoprotein (AFP) was purified by a two step method. Anti-dog AFP antiserum was produced by immunizing rabbits with canine fetal serum proteins that failed to bind to an anti-dog whole adult serum affinity column. Canine AFP was then purified from amniotic fluid using affinity chromatography with anti-dog AFP antiserum. The bound protein was then eluted and further purified by passage through an anti-dog whole adult serum column. The non-binding protein's purity and specificity was confirmed by immunoelectrophoresis, double-diffusion, sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and cross-reactivity with anti-human AFP. The molecular weight of canine AFP was approximately 66,000 by SDS-PAGE. Normal adult dogs had serum AFP levels of 7-63 ng ml-1. Levels of AFP were not altered by pregnancy but did show a small peak 2 days following parturition. Newborn puppies had serum AFP levels of 14.08 +/- 5.94 mg ml-1 at birth. By 1 week of age, serum AFP had fallen to 0.766 +/- 0.758 mg ml-1. AFP values in newborn puppies are thus considerably higher than those previously reported in humans, pigs and cattle.

An assay procedure for ornithine carbamoyl transferase (OCT), which is known to be a liver-specific enzyme, was modified to be adaptable to bovine serum. The concentration of carbamoyl phosphate and the pH of the reaction reagent solution shifted to 60 mM and 7.2, respectively. These modifications contributed to the augmentation of assay sensitivity. The day-to-day reproducibility was 7.9% (coefficient variation) for serum with high OCT activity and 14.8% for normal bovine serum. The activity was stable for 3-4 months by the storage at -20 degrees C and at least 6 months at -80 degrees C. The OCT activity and other biochemical components including aspartate aminotransferase and gamma glutamyl transpeptidase were measured in sera from 164 dairy or raising cows reared at 7 farms. The normal level of OCT activity in sera from these cows ranged from 9.2 to 25.1 U/l (mean +/- 2SD). By comparison between the farms, the highest mean value of OCT activity was found in a farm where cows were suspected to have some kind of latent liver disease from the data of other biochemical parameters. We conclude that the OCT activity is a very useful diagnostic indicator of liver disease in cattle.