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181.
Zabłotna Ewa Kaźmierczak Katarzyna Jaśkiewicz Anna Kupryszewski Gotfryd Rolka Krzysztof 《International journal of peptide research and therapeutics》2002,9(2-3):131-134
Summary Trypsin inhibitor SFTI-1 isolated from sunflower seeds (comprising 14 amino acid residues and two cycles: head-to-tail cyclisation
and disulfide bridge) is the smallest naturally occurring plant serine proteinase inhibitor. In our recent paper we have shown
that the elimination head-to-tail cyclisation did not change trypsin inhibitory activity as judged by measured by association
equilibrium constants K
a
. The removal of disulfide bridge produced 2.4-fold lower activity. In the present paper we described chymotrypsin inhibitory
activity. SFTI-1 inhibits significantly lower bovine α-chymortypsin (K
a
=(5.20±1.56)×106 M−1). The activity of the analogue with disulfide bridge only was practically the same, whereas the K
a
value determined for homodetic peptide was almost 3-fold lower. Considering the results obtained and the recent literature
data we postulate the lower inhibitory activity against both enzymes of the analogue with head-to-tail cyclisation only reflect
its lower proteolytic stability. 相似文献
182.
Czerwińska E Marcinowska-Suchowierska E Walicka M Lisik W Wierzbicki Z 《Endokrynologia Polska》2007,58(2):130-138
INTRODUCTION: Obese patients may have abnormal calcium homeostasis because of unbalanced diet and decreased sun exposure. Bariatric surgery itself may lead to disturbances in calcium homeostasis (and in consequence changes in bone mass) or increase preexisting metabolic derangements. The aim of the study was: 1. To assess calcium homeostasis and biochemical markers of bone turnover in patients with morbid obesity. 2. To determine the impact of bariatric surgery on parameters mentioned above. 3. To establish recommendations for supplementation with calcium and vitamin D in morbidly obese patients after bariatric surgery. MATERIAL AND METHODS: Serum calcium, parathormone (PTH), vitamin D (25(OH)D), biochemical markers of bone turnover (beta-CrossLaps as a marker of bone resorption and osteocalcin as a marker of bone formation) and urine calcium as well as fat mass, lean mass and bone mineral content (by DXA) were measured before bariatric surgery of the stomach (VBG or GBP) in 57 morbidly obese patients (48 women, 9 men; mean age 35.9 y). The same procedures were repeated six months after operation in 28 of them (24 women, 4 men). Daily calcium intake was also determined based on food questionnaire. RESULTS: Biochemical findings in the group of patients before bariatric surgery were as follows: serum calcium, beta-CrossLaps and urine calcium were within normal range, PTH concentration was increased to 81.0 pg/ml and 25(OH)D as well as osteocalcin concentration decreased (4.9 ng/ml and 13.6 ng/ml, respectively). Six months after bariatric surgery there was no change in serum and urine calcium, PTH concentration decreased to normal level (46.8 pg/ml), 25(OH)D concentration increased to 6.5 ng/ml (not significant) and still remained below normal range. Markers of bone turnover--both resorption and formation--increased (beta-CrossLaps over normal range to 0.594 ng/ml, osteocalcin to normal range 26.8 ng/ml). Daily calcium intake was below RDA before and after bariatric procedure. CONCLUSIONS: 1. Patients with morbid obesity have secondary hyperparathyroidism and deficiency of vitamin D. 2. Abrupt weight loss after bariatric surgery is accompanied by the regression of secondary hyperparathyroidism, decrease of the deficiency of vitamin D and increase in bone turnover. 3. Supplementation with vitamin D and calcium is recommended for patients with morbid obesity after bariatric surgery. 相似文献
183.
The induction of thymocyte apoptosis through the Nur77-mediated intrinsic pathway can be of physiological importance in the clonal deletion of autoreactive thymocytes during negative selection in the thymus and/or in thymocytes undergoing oncogenic transformation. Ionomycin treatment induces endogenous Nur77 expression as well as apoptosis and cytochrome c release in thymocytes. Here it is shown for the first time that in normal thymocytes undergoing apoptosis, ionomycin induces translocation of endogenous Nur77 not only to the nucleus, but also to mitochondria. Immunosuppressant FK506 inhibits Nur77 NBRE and NurRE binding activity but has no effect on thymocytes apoptosis, the subcellular localization of Nur77, or cytochrome c release. This indicates that thymocytes can undergo apoptosis through the intrinsic Nur77-mediated mitochondrial pathway and that the transactivation activity of Nur77 monomers or dimers is not necessary for thymocyte apoptosis. 相似文献
184.
185.
Kołodziej Barbara Kochan Ewa Kazimierczak Jerzy Chmiel Aleksander 《Plant Growth Regulation》2006,48(1):13-19
American ginseng (Panax quinquefolium L.) is a perennial medicinal herb originally grown in Canada and USA, and recently also in China, Australia, Holland and
Poland. Several commercial preparations are produced from ginseng roots, that are known for their antifatigue, antitumor,
antistress and immune system stimulating functions. The medicinal properties are due mainly to the active components – ginsenosides.
In this work, the results of field cultivation experiments are presented that examine the effects of foliar application of
several growth regulators on quality parameters and ginsenoside content of P. quinuefolium roots. The growth regulators tested, i.e., kinetin, daminozide, mixture of gibberellic acid (GA3) with potassium salt of α-naphthalene acetic acid (kNAA) and new preparation – IPO-1 – benzimidazole derivative (obtained
from the Institute of Organic Industry in Warsaw – at present during the process of patent), were applied at a concentration
of 100 or 200 mg l−1 in the middle of June in the 2nd year of vegetation. After 4 years of cultivation, the roots were dug up and dried, and subsequently
the quantitative analysis of individual saponins (Rb1, Rb2, Rc, Rd, Re, Rg1) by HPLC was performed. Growth regulators significantly affected quality parameters, morphological features and accumulation
of individual and total ginsenosides in ginseng roots. Regardless of doses, the plant roots treated with growth regulators
had a higher content of total ginsenosides in comparison to the control. The growth regulators also affected individual ginsenosides
level and narrowed the ratio of Rb:Rg group. The application of kinetin, daminozide and benzimidazole derivative for foliar spray during 2nd year of American ginseng
vegetation caused a significant increase in air dry weight of roots and aboveground parts whereas the mixture of GA3 and kNAA showed a decreasing effect. An increase of roots size was observed using higher doses (200 mg l−1) of kinetin and daminozide while a decreasing tendency appeared with the application of the other preparations. 相似文献
186.
Anaplasma phagocytophilum,Babesia microti,Borrelia burgdorferi sensu lato,and Toxoplasma gondii in Ixodes ricinus (Acari,Ixodida) ticks collected from Slowinski National Park (Northern Poland) 下载免费PDF全文
187.
188.
189.
Enhanced production of the pharmaceutically important polyphenolic compounds in Vitex agnus castus L. shoot cultures by precursor feeding strategy 下载免费PDF全文
Ewa Skrzypczak‐Pietraszek Kamil Piska Jacek Pietraszek 《Engineering in Life Science》2018,18(5):287-297
Agitated Vitex agnus castus L. shoot cultures were established to analyse the content of selected pharmaceutically important flavonoids and phenolic acids. Two variants (selected from nine ones) of MS medium were prepared: A (BAP 1 mg/L; NAA 0.5 mg/L; GA3 0.25 mg/L) and B (BAP 2 mg/L; NAA 0.5 mg/L). The biomass was harvested after 1, 2, 3,4, 5 and 6 weeks. Four‐week cultures (variant A) were selected to perform the precursor feeding experiment. The L‐phenylalanine dose of 1.6 g/L appears to be the most advantageous. Compared to the control cultures, the content of the individual compounds increased in a range from 1.4 to 17.3‐fold (e.g. p‐coumaric acid – 17.3 fold; casticin – 4.8‐fold). The biomass from in vitro cultures is richer in neochlorogenic acid (16‐fold), p‐coumaric acid (5.3‐fold), rutin (2.8‐fold), caffeic acid (1.5‐fold) and cinaroside (1.5‐fold) than the leaves of its parent greenhouse‐cultivated plants. Extracts contained 30 mg/100 g DW of casticin, but after the hydrolysis its amount increased up to 200 mg/100 g DW and twice exceeded the content in the greenhouse leaves. The results indicate that V. agnus castus agitated shoot cultures might be considered as a potential biotechnological source of some pharmaceutically important compounds, especially casticin, rutin, neochlorogenic and p‐coumaric acids. 相似文献
190.
Ewa Hanus-Fajerska Maria Lech Anna Pindel Kazimierz Miczyński 《Acta Physiologiae Plantarum》2000,22(3):317-324
Protocols elaborated with the objective of achieving valuable material for selection procedure of variants with virusresistance
traits in tomato genotypes are presented. Preliminary results are demonstrated in the domain of testing for variability in
somaclones obtained through indirect adventitous organogenesis initiated on leaf explants of cultivated tomato (Lycopersicon esculentum Mill.). Somaclones were grown in greenhouse conditions and variation of their symptoms upon infection with tomato mosaic
(ToMV) or cucumber mosaic (CMV) respectively was observed. Tests for resistance to the local isolates of the above cited viruses
were performed using enzyme linked immunosorbent assay and back inoculation onto diagnostic plants. Screening data are presented.
Desirable variants were selected from cultivars ‘Moneymaker’, ‘Potentat’ and ‘Rutgers’. Some of the ‘Moneymaker’ somaclones
exhibited increased tolerance to cucumber mosaic virus, a few seemed to be even fully resistant though most were susceptible
as donor plants. The most favourable somaclonal lines are actually further tested and monitored for changes in horticultural
characteristics. The described procedure of searching for resistance trait in specific pathogen-free (SPF) plants regenerated
from infected tissue looks promising and thus can serve as aid in attaining appropriate objectives of breeding programme.
Additionaly experiments were initiated to obtain somaclones from cultivars ‘Beta’, ‘Krakus’ and Stevens Rodade hybrid via
regeneration of isolated protoplasts. To this end the callus stage was obtained from all donors. 相似文献