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Manganese octahedral molecular sieves with an α-MnO 2 crystal structure (OMS-2) and their related materials have attracted significant attention for the selective catalytic reduction of NO x using NH 3 (NH 3 -SCR) at low temperatures. Further lowering their operating temperature should be an effective method to develop an environmentally friendly de-NO x system; however, their catalytic activity at low temperatures, especially below 100 °C, remains poor. This study describes a post-synthetic approach to develop Mn-based catalysts superior to those in the literature that operate at ultralow temperatures. Post-synthetic planetary ball milling for OMS-2 caused the partial conversion of OMS-2 into β-MnOOH. The obtained nanocomposite catalysts possessed abundant surface oxygen vacancies and strong surface acidity, allowing the milled catalyst to exhibit higher NO conversion at 90 °C (91%) than that in freshly prepared OMS-2 without planetary ball milling (29%). Lowering the operation temperature of OMS-2 catalysts contributed to the suppression of N 2 O evolution during NH 3 -SCR over manganese-based catalysts, resulting in high N 2 selectivity over the milled OMS-2 catalyst (93%)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The low temperature activity of Fe-loaded zeolites as selective catalytic reduction of NO x by NH 3 (NH 3 -SCR) catalysts is a critical drawback for practical application. Here, we found unexpected improvement of low temperature activity by our proposed post-synthetic treatment. An Al-rich zeolite beta (Si/Al=5) is employed as the catalyst support, and the parent sample is dealuminated for higher hydrothermal stability, followed by the liquid-mediated stabilization treatment and impregnation. It is found that stabilized samples feature excellent low temperature activity and high N 2 selectivity even for a long-term operation, along with the ability to maintain high NO x conversion after aging. The improved SCR activity should be attributed to abundant acid sites in Al-rich framework and better stabilization of monomeric iron species after the stabilization treatment. Furthermore, the low yield of side product N 2 O is probably due to the absence of the generation of NH 4 NO 3 during NH 3 -SCR catalyzed by Fe-loaded zeolites., (© 2023 Wiley-VCH GmbH.)

In order to establish a standard analytical method for the determination of trace amounts of tin and lead in magnesium and its alloys, which could be found in neither JIS nor ISO standards, an interlaboratory testing with inductively coupled plasma atomic emission spectrometry (ICP-AES) has been put into practice. Simple dissolution with nitric and hydrochloric acids and sample nebulization procedures were finally concluded to be suitable for standardization. The analytical methods, proposed in this study have been provided as newly established JIS standards.

The retinoblastoma tumor suppressor (Rb) gene product plays an essential role in cell-cycle regulation. However, its role in terminal differentiation of hematopoietic cells is speculative. Here we show a model of 12-o-tetradecanoylphorbol-13-acetate (TPA)-induced hematopoietic differentiation and growth arrest with a defective Rb-mediated pathway. TPA treatment arrested the cell cycle of a human hematopoietic cell line, MEG-01s, at the G1-S boundary and induced expression of p21/SDI1/WAF1/CIP1 and p27/KIP1. Both of these proteins were present in cyclin E-associated complexes, the histone H1 and Rb kinase activities of which were then inactivated. However, MEG-01s cells lacked the intact Rb protein and the Rb-mediated pathway was defective. This model raises a question about the role for Rb in terminal differentiation of hematopoietic cells.

To analyze the pulsatile movement of coronary arterial walls, intravascular ultrasound was used to measure the diameter changes in the arterial lumen of 32 patients with coronary artery disease (CAD group) and five patients with chest pain but no CAD (control group). Measurements were performed on segments of the proximal left anterior descending coronary artery that were angiographically nonstenotic. Following identification of the peak systolic and end-diastolic phases using intra-coronary pressure tracings, the luminal diameters were measured around the center at 4 degrees intervals using a computer-assisted image analyzer. The pulsatile diameter change (dD) and end-diastolic diameter (DD) at each interval were analyzed and compared between the CAD and control groups. Mean DD did not differ significantly between the CAD group (4.53 +/- 0.69 mm) and the control group (4.52 +/- 0.51 mm). In contrast, the mean dD in the CAD group (0.05 +/- 0.18 mm) was significantly lower than that of the control group (0.13 +/- 0.12 mm). The mean maximum and minimum standardized percentage pulsatile diameter changes were -10.6 +/- 6.2% and 16.2 +/- 5.9%, respectively, in the CAD group, and -2.7 +/- 4.6% and 11.7 +/- 1.3%, respectively, in the control group. The mean standard deviation of dD was significantly greater in the CAD group (0.182 +/- 0.05 mm) than in the control group (0.116 +/- 0.04 mm), which indicated dD in CAD patients varied to a greater degree than in control patients. The ratio dD/dP (dP : pulse pressure) was used as an index of vascular compliance at the site of measurement. The mean dD/dP was significantly smaller in the CAD group (1.1 +/- 2.5 x 10(-3) mm/mmHg) than in the control group (4.0 +/- 3.3 x 10(-3) mm/mmHg). Aniso-diametric wall movement in the coronary artery (as indicated by a negative dD during systolic expansion) was enhanced in the CAD group compared to the control group. This was probably caused by the early stages of the arterial sclerotic process as it progressed heterogeneously along the vessel wall. Thus, aniso-diametric movement, which is a functional abnormality of the coronary arterial wall, appears to antedate detectable morphological changes.

Cyclin D1 is one of the key regulators in G1 progression in the cell cycle and is also a candidate oncogene (termed PRAD1 or bcl-1) in several types of human tumors. We report a collaboration of the cyclin D1 gene with ras and a mutated form of p53 (p53-mt) in neoplastic transformation. Transfection of cyclin D1 alone or in combination with ras or with p53-mt was not sufficient for focus formation of rat embryonic fibroblasts. However, focus formation induced by co-transfection of ras and p53-mt was enhanced in the presence of the cyclin D1-expression plasmid. Co-transfection of ras- and p53-mt-transformants with the cyclin D1-expression plasmid resulted in reduced serum dependency in vitro. Furthermore, the transformants expressing exogenous cyclin D1 grew faster than those without the cyclin D1 plasmid when injected into nude mice. These observations strengthen the significance of cyclin D1 overexpression through gene rearrangement or gene amplification observed in human tumors as a step in multistep oncogenesis; deregulated expression of cyclin D1 may reduce the requirement for growth factors and may stimulate in vivo growth.

The authors surveyed the prevalence of depression and dementia in the elderly in Ohira town in Japan from 1989 to 1990. The total population of this town was 26,712, with 2,778 people aged 65 and above, constituting 10.4% of the total population. The prevalence of dementia (n = 128) was 6.1% and that of major depression (n = 9) was 0.4%, according to the DSM-III-R criteria. The prevalence of a depressive state which did not fulfill the criteria for major depression (n = 55) was 2.4%. The patients with multi-infarct dementia (n = 49) suffered from depression (42.8%) more frequently than those with dementia of the Alzheimer type (11.1%). The rate of depression coexisting with dementia increased with aging, while the rate of depression without dementia did not change in all the age groups.

The clinical evaluation of exercise in elderly NIDDM was investigated with the following. Based on the questionnares filled in by 508 patients with NIDDM regarding whether they had regular exercise for treatment of diabetes mellitus or not, 53.4% and 41.4% of NIDDM men obtained regular exercise in the 30-40 and 50-59 age groups, respectively. On the other hand, the figures for the 60-69 and over 70 age groups were 67.0% and 73.3%, respectively. From these data, regular exercise in elderly NIDDM men was significantly more frequent than in middle aged NIDDM men. No similar tendency in NIDDM women was found. Regular exercise as a therapeutic approach was lowest in the insulin group compared to other types of therapy. We investigated heart rate pressure product, work rate, volume of oxygen uptake at anaerobic threshold (AT) during exercise on bicycle ergometer. These parameters in elderly NIDDM men and women aged over 60 were significantly lower compared to young and middle aged cases of NIDDM. But these clinical parameters at the anaerobic threshold (AT) after exercise training were significantly improved in work rate and blood pressure as compared to data before exercise training. We compared the effects of exercise at an intensity of AF for 30 minutes on glucose metabolism between middle aged and elderly NIDDM. Levels of blood glucose in elderly NIDDM after exercise was not changed, whereas that in middle aged NIDDM after exercise was significantly decreased. From the present study, many clinical differences were seen between elderly and young NIDDM.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of crossed total hemiatrophy (right side of the face, and left side of the trunk and left extremities) with a right precentral to central arteriovenous malformation is reported. The atrophy of trunk and extremities was well accounted for by the contralateral arteriovenous malformation, but a pathological early auditory response was the only brainstem sign possibly related to the facial atrophy.