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81.
Effect of plant growth regulators on in vitro fiber development from unfertilized and fertilized Egyptian cotton ovules 总被引:2,自引:0,他引:2
Osama A. Momtaz 《Plant Growth Regulation》1998,25(3):159-164
Unfertilized and fertilized ovules of Gossypium barbadense Giza 45 (extra long staple variety) were used to study the effect of plant growth substances (auxins, gibberellins and cytokinins) on in vitro fiber initiation and development. Kinetin, alone did not increase total fiber unit (TFU) of unfertilized ovules, while an increase in TFU value occurred when a constant level of IAA and GA3 were used either separately or in combination in the liquid medium. GA3 used alone, produced a higher TFU value than that produced by IAA, whilst, IAA with a constant level of GA3 (5 M) produced the highest value of TFU. GA3 with a constant level of IAA (5 M) produced a lower TFU value. Kinetin reduced the stimulatory effect of IAA and GA3 on TFU value when used in combination with either substance. In fertilized ovules, the highest level of TFU was reached when IAA, with a constant level of GA3, was added to the medium, whilst its lowest level was obtained when IAA was used alone. Estimation of in vitro fiber production, as well as the effect of growth substances used in different concentrations on in vitro fiber initiation and development from unfertilized and fertilized ovules of Egyptian cotton varieties Gossypium barbadense Giza 45 are discussed. 相似文献
82.
Manal M. Elbandrawy Osama Sweef Doaa Elgamal Tarek M. Mohamed EhabTousson Rehab M. Elgharabawy 《Saudi Journal of Biological Sciences》2022,29(5):3871
BackgroundType 2 diabetes (T2DM) is a chronic metabolic disorder. Although therapeutic pharmaceutical agents continue to advance, herbal medicines are potential complementary treatments for the promotion of glucose homeostasis, with minimal adverse effects. Conventionally, ellagic acid (EA) has been utilized for the therapy of a range of pathologies owing to its anti-inflammatory and anti-diabetic actions.ObjectiveThe aim of this study is to determine the activity of EA on serum α-amylase and lipase titers, and on pancreatic tumor necrosis factor-α (TNF-α), proliferating cell nuclear antigen (PCNA) and interleukin-6 (IL-6) concentrations using the streptozocin-induced T2DM rodent model.MethodsEA extract synthesized from fresh strawberry fruit was employed for therapy. 50 adults male Wistar rats were randomized into either control, EA, diabetic, co-treated or post- treated cohorts.ResultsEA diminished fasting blood glucose levels, altered lipase, amylase, IL-6, PCNA and TNF- α expression and enhanced islet cell renewal, insulin, and immunoreactivities.ConclusionInflammatory indicators are elevated in the presence of T2DM. Extract of EA has overall tissue reparative and safeguarding properties, as indicated by the augmented β- cell population and enhanced glucose homeostasis. Thus, EA may be an innovative treatment approach for the maintenance of normoglycemia in individuals with T2DM. 相似文献
83.
Andrew H. Fischer Chengquan Zhao Qing Kay Li Karen S. Gustafson Isam‐Eldin Eltoum Rosemary Tambouret Barbara Benstein Lynnette C. Savaloja Peter Kulesza 《Journal of cellular biochemistry》2010,110(4):795-811
Cytology and cell biology are two separate fields that share a focus on cancer. Cancer is still diagnosed based on morphology, and surprisingly little is known about the molecular basis of the defining structural features. Cytology uses the smallest possible biopsy for diagnosis by reducing morphologic “criteria of malignancy” to the smallest scale. To begin to develop common ground, members of the American Society of Cytopathology Cell Biology Liaison Working Group classify some of the “criteria of malignancy” and review their relation to current cell biology concepts. The criteria of malignancy are extremely varied, apparently reflecting many different pathophysiologies in specific microenvironments. Criteria in Group 1 comprise tissue‐level alterations that appear to relate to resistance to anoikis, alterations in cell adhesion molecules, and loss of apical–basal polarity. Criteria in Group 2 reflect genetic instability, including chromosomal and possibly epigenetic instability. Criteria in Groups 3 are subcellular structural changes involving cytoplasmic components, nuclear lamina, chromatin and nucleoli that cannot be accounted for by genetic instability. Some distinct criteria in Group 3 are known to be induced by cancer genes, but their precise structural basis remains obscure. The criteria of malignancy are not closely related to the histogenetic classification of cancers, and they appear to provide an alternative, biologically relevant framework for establishing common ground between cytologists and cell biologists. To understand the criteria of malignancy at a molecular level would improve diagnosis, and likely point to novel cell physiologies that are not encompassed by current cell biology concepts. J. Cell. Biochem. 110: 795–811, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
84.
85.
Badary OA AbdEl-Gawad HM Taha RA Ali AA Hamada FM 《Journal of biochemical and molecular toxicology》2003,17(2):86-91
The effects of benzo[a]pyrene (B[a]P) on some drug-metabolizing and antioxidant systems in liver, lung, and stomach were investigated in normal and protein malnutrition (PM) rats. PM significantly inhibited tissue glutathione (GSH) content and increased hepatic lipid peroxidation. Cytochrome P450 isoform CYP1A1 was significantly increased in various tissues (42-73%). Also, lung glutathione S-transferase (GST) activity was significantly decreased (19%) in PM rats. On the other hand, B[a]P significantly induced tissue GSH of control and PM rats. Also, hepatic lipid peroxidation were significantly increased in control rats treated with B[a]P. Superoxide dismutase (SOD) activity was decreased by B[a]P treatment in PM rat stomach. B[a]P significantly induced both quinone reductase (QR) (in all tissues) and hepatic GST of control and PM rats. GST activity in PM rat liver was significantly higher than that of control rat liver after B[a]P treatment. Also, B[a]P induced hepatic CYP1A1 by 32-fold and 27-fold (P < or = 0.05) in control and PM rats, respectively. Stomach and hepatic UDP-glucuronosyltransferase activities were significantly decreased (34%) and increased (74%), respectively by B[a]P in PM rats. The results suggest that PM status has a modifying effect on the response of some antioxidant and metabolizing systems to a well-known carcinogen risk. 相似文献
86.
Osama Omar Yousif Mea’ad Kadhum Hassan Lamia Mustafa Al-Naama 《Biological trace element research》2018,182(2):295-302
This study investigated neurotoxicity of chronic fluorosis in the rat hippocampus. Newly weaning, male, Sprague-Dawley (SD) rats were administered 15, 30, and 60 mg/L sodium fluoride (NaF) solution (fluorine ion concentration 8.25, 16.50, and 33.00 mg/L, respectively), and tap water, for 18 months. The neurotoxicological mechanism was examined with a focus on intracellular calcium overload. Results showed that as the fluoride concentration increased, calcium ion concentration [Ca2+], the expression of calcium/calmodulin-dependent protein kinase II α (CaMKIIα), and the expression of catus proto-oncogene protein c-fos (c-fos) all tend to increase. Compared to the control group, Ca2+, CaMKIIα, and c-fos significantly increased (P < 0.05) in the moderate-fluoride and the high-fluoride groups. These results indicate that Ca2+/CaMKIIα/c-fos channel signal may be the molecular mechanism of central nervous system damage caused by chronic fluoride intoxication. Moreover, elevated Ca2+ concentration in the hippocampus may be the initiating factor of neuronal apoptosis induced by fluoride. 相似文献
87.
Photophysical properties of hydroxyphenyl benzazoles and their applications as fluorescent probes to study local environment in DNA,protein and lipid 下载免费PDF全文
Fluorescence techniques have drawn increasing attention because they provide crucial information about molecular interactions in protein–ligand systems beyond that obtained by other methods. The advantage of fluorescence spectroscopy stems from the fact that the majority of molecules in biological systems do not exhibit fluorescence, making fluorescent probes useful with high sensitivity. Also, the fluorescence emission is highly sensitive to the local environment, providing a valuable tool to investigate the nature of binding sites in macromolecules. In this review, we discuss some of the important applications of a class of molecules that have been used as fluorescent probes in a variety of studies. Hydroxyphenyl benzazoles (HBXs) show distinct spectroscopic features that make them suitable probes for the study of certain biological mechanisms in DNA, protein and lipid. In particular, the complex photophysics of 2‐(2′‐hydroxyphenyl)benzoxazole (HBO) and the distinguished fluorescence signatures of its different tautomeric forms make this molecule a useful probe in several applications. Among these are probing the DNA local environment, study of the flexibility and specificity of protein‐binding sites, and detecting the heterogeneity and ionization ability of the head groups of different lipidic phases. The spectroscopy of HBX molecules and some of their chemically modified structures is also reviewed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
88.
Hany Ahmed Fouad Hosam Mohamed Khalil Hammam El-Gepaly Osama Ahmed Fouad 《Archives Of Phytopathology And Plant Protection》2016,49(13-14):362-370
Recently, Tuta absoluta became one of the major pests that attack commercial tomato globally. Field test was done to evaluate the effect of different concentrations of nanosilica (NS) and jasmonic acid (JA), and compared them with indoxacrb (recommended insecticide) on reduction of damage rate caused by T. absoluta larvae under field conditions. Nanosilica (600 ppm) and indoxacrb (0.25 cm3/L) had the highest efficiency to reduce the rate of mines in the leaves. Jasmonic acid at rate 1.141 μM/plant showed a good reduction of number of fruits damaged. Nanosilica with 600 ppm concentration and Jasmonic acid at rate 1.141 μM/plant is used to control T. absoluta in the field. 相似文献
89.
Marie-Charlott Rümmler Osama Mustafa Jakob Maercker Hans-Ulrich Peter Jan Esefeld 《Polar Biology》2016,39(7):1329-1334
Unmanned aerial vehicles (UAVs) have become a useful tool in polar research. While their performance is already proven, little is known about their impact on wildlife. To assess the disturbance caused on the penguins, flights with a UAV were conducted over an Adélie penguin (Pygoscelis adeliae) colony. Vertical and horizontal flights were performed between 10 and 50 m in altitude. Penguins’ reactions were video-recorded, and the behavioural response was used to indicate the level of disturbance. During any flight mode, disturbance increased immediately after takeoff and remained elevated at all altitudes between 20 and 50 m. When the UAV descended below 20 m, the disturbance increased further with almost all individuals being vigilant. Only at these low altitudes, vertical flights caused an even higher level of disturbance than horizontal ones. Repetitions of horizontal overflights showed no short-term habituation occurring. Since the results are only valid for the specific UAV model used, we recommend a more extensive approach with different UAV specifications. As the highest flight altitudes already caused detectable but not subjectively visible responses, we also recommend to regard subjective impressions of disturbance with caution. 相似文献
90.
Summary A local strain of Asp. phoenicis proved to be a good gluconic acid producer. Previous experiments carried out on this organism were extended to investigate the influence of some culture conditions on the acid production when the submerged technique was applied. These included the investigation of the influence of the nature and concentration of the nutritive constituents of the fermentation medium. 相似文献