Raman spectroscopic study of hydrogen bonding of poly(N-vinyl-2-pyrrolidone) in heavy water and dimethyl sulfoxide

The Raman spectra of solutions of poly(N-vinyl-2-pyrrolidone) (PVP; M?_w = 1 000, 10 000, 40 000 and 360 000) in D₂O and dimethyl sulfoxide (DMSO) were measured at various concentrations. PVP is hydrated by D₂O in a manner different from N-ethyl-2-pyrrolidone (NEP) and N-methyl-2-pyrrolidone (NMP), monomer analogues of PVP. The self-association of DMSO molecules in the solution of PVP was found to be different from that in the solution of NMP by using difference spectroscopy. These phenomena were attributed to a net-like structure of concentrated solutions of PVP.     

Cytogenetic studies of Hynobiidae (Urodela) XIX. Morphological variation of sex chromosomes pairing behavior of sex lampbrush chromosomes in <Emphasis Type="Italic">Hynobius quelpaertensis</Emphasis> (Mori) from Cheju Island,South Korea

Using Giemsa staining, C-banding and Ag-NOR staining techniques, we analyzed chromosomes in adult male and female Hynobius quelpaertensis and in embryos of this species in egg sacs collected from eight localities of Cheju Island, South Korea. Chromosome pair 21 was consistently homomorphic in male specimens, while it was heteromorphic in female specimens, suggesting the occurrence of ZZ/ZW sex chromosome constitution in this species. The W chromosome, being much larger than the Z chromosome, was of three morphologically distinct types: W^A, W^B and W^C. Lampbrush chromosomes examined in the oocytes of one female specimen having the W^A chromosome showed that the short arm of the W^A chromosome and the long arm of the Z chromosome paired closely and hence are genetically homologous. We also tried to analyze the structural relationship among the three types of W chromosomes based on their C-banding and Ag-NOR patterns.     

M pathway and areas 44 and 45 are involved in stereoscopic recognition based on binocular disparity

We characterized the visual pathways involved in the stereoscopic recognition of the random dot stereogram based on the binocular disparity employing a functional magnetic resonance imaging (fMRI). The V2, V3, V4, V5, intraparietal sulcus (IPS) and the superior temporal sulcus (STS) were significantly activated during the binocular stereopsis, but the inferotemporal gyrus (ITG) was not activated. Thus a human M pathway may be part of a network involved in the stereoscopic processing based on the binocular disparity. It is intriguing that areas 44 (Broca's area) and 45 in the left hemisphere were also active during the binocular stereopsis. However, it was reported that these regions were inactive during the monocular stereopsis. To separate the specific responses directly caused by the stereoscopic recognition process from the nonspecific ones caused by the memory load or the intention, we designed a novel frequency labeled tasks (FLT) sequence. The functional MRI using the FLT indicated that the activation of areas 44 and 45 is correlated with the stereoscopic recognition based on the binocular disparity but not with the intention artifacts, suggesting that areas 44 and 45 play an essential role in the binocular disparity.     

Effects of participatory workplace improvement program on stress-related biomarkers and self-reported stress among university hospital nurses: a preliminary study

Although participatory workplace improvement programs are known to provide favorable effects on high stress occupations like nursing, no studies have confirmed its effect using biomarkers. The aim of this study was to determine whether a participatory workplace improvement program would decrease stress-related symptoms as evaluated by biomarkers and self-reported stress among hospital nurses. Three actions to alleviate job stress, which were determined through focus group interviews and voting, were undertaken for two months. A total of 31 female Japanese nurses underwent measurement of inflammatory markers, autonomic nervous activity (ANA), and perceived job stress (PJS) at three-time points; before the program (T1), within a week after the completion of the program (T2), and three months after the program (T3). A series of inflammatory markers (Interferon-γ, Interleukin (IL)-6, and IL-12/23p40) decreased significantly at T2, and IL-12/23p40 and IL-15 significantly decreased at T3 compared to T1, while ANA and PJS remained unchanged. Our participatory program exerted beneficial effects in reducing inflammatory responses, but not for ANA and PJS. Further investigations with a better study design, i.e., a randomized controlled trial, and a larger sample size are warranted to determine what exerted beneficial effects on inflammatory markers and why other outcomes remained unchanged.     

A cost-minimization analysis of measures against metallic dental restorations for head and neck radiotherapy

The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals.     

Characterization of [3H]brevetoxin binding to voltage-dependent sodium channels in adrenal medullary cells

We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced ²²Na influx when given alone, but increases the influx of ²²Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [³H]PbTx-3 binding in bovine adrenal chromaffin cells. [³H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (K_d) of 32.0±4.9 nmol/1 and a maximum binding capacity B_max of 6.2 ± 1.2 pmol/4 × 10⁶ cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [³H]PbTx-3 binding with an IC₅₀ of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [³H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells. Correspondence to: A. Wada at the above address     

Evaluation of a new solution containg trehalose for twenty-hour canine lung preservation

We examined the efficacy of two new preservation solutions containing trehalose-an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution — in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n=5 for each solution) after pretreatment with PGE₁ (20 g/kg) and were stored for 20 h at 4°C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.     

Comparative study on the cardio-respiratory change during prostaglandin E1-induced hypotension in the patients in the supine and prone position

Prostaglandin E₁-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE₁ was considerably lower in group II than in group I (0.067µg·kg^–1·min^–1 vs. 0.119µg·kg^–1·min^–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE₁-induced hypotension. Such a high dose of PGE₁ (0.119µg·kg^–1·min^–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE₁-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE₁-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE₁ can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E₁-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)