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51.
During two investigation periods in transient seasons (14 weekdays in autumn 2009 and 15 weekdays in spring 2010) 967 visitors in two inner city squares of Szeged (Hungary) were asked about their estimation of their thermal environment. Interrelationships of subjective assessments—thermal sensation, perceptions and preferences for individual climate parameters—were analyzed, as well as their connections with the prevailing thermal conditions [air temperature, relative humidity, wind velocity, mean radiant temperature and physiologically equivalent temperature (PET)]. Thermal sensation showed strong positive relationships with air temperature and solar radiation perception, while wind velocity and air humidity perception had a negative (and weaker) impact. If a parameter was perceived to be low or weak, then it was usually desired to be higher or stronger. This negative correlation was weakest in the case of humidity. Of the basic meteorological parameters, Hungarians are most sensitive to variations in wind. Above PET?=?29°C, people usually prefer lower air temperature and less solar radiation. The temperature values perceived by the interviewees correlated stronger with PET, but their means were more similar to air temperature. It was also found that the mean thermal sensation of Hungarians in transient seasons depends on PET according to a quadratic function (R 2?=?0.912) and, consequently, the thermal comfort ranges of the locals differ from that usually adopted. 相似文献
52.
Bernard L. Epel Jan W. M. van Lent Lilla Cohen Guy Kotlizky Aviva Katz Avital Yahalom 《Protoplasma》1996,191(1-2):70-78
Summary Plasmodesmata, dynamic pore structures that traverse plant cell walls, function in cytoplasmic transport between contiguous cells. Cell walls containing embedded plasmodesmata were isolated from mesocotyls of etiolated maize seedlings. Proteins associated with the isolated walls were separated by SDS-PAGE and antibodies were generated against a 41 kDa protein, one of several associated with this wall fraction. Immunoblot analysis showed that the 41 kDa polypeptide was also associated with other subcellular fractions obtained following tissue homogenization and differential centrifugation. The wall associated 41 kDa protein is apparently a peripheral membrane protein since it could be extracted by high salt and high pH. Silver-enhanced immunogold light microscopy showed that the 41 kDa protein was associated with the cell walls of cells both in the stele and cortex. The immunolabeling pattern was transwall and punctate. Electron microscopic immuno-gold labeling localized the polypeptide to plasmodesmata and to electron dense cytoplasmic structures that are apparently Golgi membranes. The significance of the presence of this protein in the Golgi is discussed.Abbreviations ER
endoplasmic reticulum 相似文献
53.
Root cultures of Tagetes patula L. cv. Carmen were grown with a mixture of unlabeled glucose and [U-(13)C(6)]glucose or [1-(13)C(1)]glucose as carbon source. Isoeuparin and (-)-4-hydroxytremetone were isolated by solvent extraction of the cultured tissue, purified by chromatography and analysed by (1)H and (13)C NMR spectroscopy. Amino acids obtained by hydrolysis of protein from the same experiments were used for the reconstruction of the labelling patterns in central metabolic intermediates. These labelling patterns were used for the prediction of isotopolog compositions in the benzofuranone derivatives via different hypothetical pathways. Comparison with the experimentally observed isotopolog distributions showed that the benzenoid ring and the acetoxy group are exclusively or predominantly (>98%) derived from phenylalanine and not from acetyl-CoA via a polyketide-type biosynthesis. The isopropylidene side chain and two carbon atoms of the furan and dihydrofuran moiety, respectively, originate from an isoprenoid building block obtained exclusively or predominantly (>98%) via the deoxyxylulose phosphate pathway. The exomethylene atom of the isopropylidene side chain is biosynthetically equivalent to the (Z)-methyl group of dimethylallyl diphosphate. The data indicate that isoeuparin and (-)-4-hydroxytremetone are assembled from 4-hydroxyacetophenone and dimethylallyl diphosphate via prenyl-substituted 4-hydroxyacetophenone and dihydrobenzofurans as intermediates. 相似文献
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This study was designed to explore the effect of P2X7 receptor (P2X7R) activation on the expression of p38 MAP kinase (p38 MAPK) enzyme in hippocampal slices of wild-type (WT) and P2X7R−/− mice using the Western blot technique and to clarify its role in P2X7 receptor mediated [3H]glutamate release. ATP (1 mM) and the P2X7R agonist BzATP (100 μM) significantly increased p38 MAPK phosphorylation in WT mice, and these effects were absent in the hippocampal slices of P2X7R−/− mice. Both ATP- and BzATP-induced p38 MAPK phosphorylations were sensitive to the p38 MAP kinase inhibitor, SB203580 (1 μM). ATP elicited [3H]glutamate release from hippocampal slices, which was significantly attenuated by SB203580 (1 μM) but not by the extracellular signal-regulated kinase (ERK1/2) inhibitor, PD098095 (10 μM). Consequently, we suggest that P2X7Rs and p38 MAPK are involved in the stimulatory effect of ATP on glutamate release in the hippocampal slices of WT mice. 相似文献
57.
Effects of the cyclooxygenase inhibitors indomethacin, naproxen and the thromboxane synthetase inhibitor imidazole on renal sodium water and p-aminohippurate excretion were investigated in sodium loaded conscious rats of different ages. Renal and intrarenal blood flow were studied in anaesthetized adult rats. Indomethacin and naproxen reduced PAH excretion in 5- and 10-day-old rats but not in rats of older ages. Imidazole failed to influence PAH-excretion in young animals. The excretion of PAH was decreased in adult rats at 10 and 60 min following imidazole administration, but not after longer time interval (120 min). Following indomethacin and naproxen administration urine output was decreased in 5-, 10- and 15-day-old rats, but not in rats of older ages. Effects of imidazole on electrolyte excretion can be demonstrated in adult rats only. Cardiac output was not altered by the three drugs. Blood pressure was elevated after indomethacin, but remained unchanged after naproxen and imidazole treatment. Renal and cortical blood flow remained unaltered and no redistribution was seen in intrarenal blood flow after indomethacin, naproxen and imidazole administration. The experimental data suggest that prostaglandins and thromboxanes are involved in the regulation of kidney function, but prostaglandins in the rat--in contrast to the dog--do not seem to play a major role in the regulation of renal vascular tone in adult animals. 相似文献
58.
Lilla Tamási Anikó Bohács Viola Tamási Balázs Stenczer Zoltán Prohászka János RigóJr. György Losonczy Attila Molvarec 《Cell stress & chaperones》2010,15(3):295-300
Asthma is one of the most common diseases complicating pregnancy and represents a risk factor for several maternal and perinatal
complications. The natural history of asthma is known to change in pregnancy, but very few data are available in the terms
of pathomechanism of this change during gestation. Circulating heat shock protein 70 (Hsp70) levels are decreased in healthy
pregnancy, which might reflect physiological immunotolerance. The aim of our study was to determine the serum levels of Hsp70
in asthmatic women during gestation. Forty pregnant women with bronchial asthma and 40 healthy pregnant women matched for
maternal and gestational age were involved in this case-control study. Serum Hsp70 levels were measured using the ELISA Kit
of R&D Systems. Spirometry and oxygen saturation measurements were performed in asthmatic patients. In asthmatic pregnant
women, an increase of serum Hsp70 levels was observed compared to healthy pregnant women (median (25–75 percentile): 0.44 ng/ml
(0.36–0.53) versus 0.21 ng/ml (0–0.27), p < 0.001). Fetal birth weight of asthmatic mothers was significantly smaller than of healthy controls, but in the normal range
(3,230 g (2,690–3,550) versus 3,550 g (3,450–3,775), p < 0.05). A statistically significant negative correlation between maternal age and serum Hsp70 concentrations (Spearman R = −0.48, p = 0.0018) and a significant positive correlation between gestational age and serum Hsp70 levels (Spearman R = 0.83, p < 0.001) were detected in healthy pregnant women. In conclusion, this study proves an elevation of circulating Hsp70 levels
during asthmatic pregnancy compared to healthy pregnant women. However, further studies are warranted to determine the role
of circulating Hsp70 in the pathogenesis of maternal and perinatal complications of asthma in pregnancy. 相似文献
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60.
Jayendrakishore Tanjore Ramanathan Suvi Lehtipuro Harri Sihto Jzsef Tvri Lilla Reiniger Vanda Tglsi Judit Moldvay Matti Nykter Hannu Haapasalo Vadim Le Joncour Pirjo Laakkonen 《Journal of cellular and molecular medicine》2020,24(12):6916-6927
Glioblastomas and brain metastases (BM) of solid tumours are the most common central nervous system neoplasms associated with very unfavourable prognosis. In this study, we report the association of prostate‐specific membrane antigen (PSMA) with various clinical parameters in a large cohort of primary and secondary brain tumours. A tissue microarray containing 371 cases of ascending grades of gliomas pertaining to astrocytic origin and samples of 52 cases of primary lung carcinomas with matching BM with follow‐up time accounting to 10.4 years was evaluated for PSMA expression using immunohistochemistry. In addition, PSMA expression was studied in BM arising from melanomas and breast carcinomas. Neovascular expression of PSMA was evident alongside with high expression in the proliferating microvasculature of glioblastomas when compared to the tumour cell expression. This result correlated with the results obtained from the in silico (cancer genome databases) analyses. In gliomas, only the vascular expression of PSMA associated with poor overall survival but not the tumour cell expression. In the matched primary lung cancers and their BM (n = 52), vascular PSMA expression in primary tumours associated with significantly accelerated metastatic dissemination to the brain with a tendency towards poor overall survival. Taken together, we report that the vascular expression of PSMA in the primary and secondary brain tumours globally associates with the malignant progression and poor outcome of the patients. 相似文献