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1.
A new species of Hirschmanniella was found in bulrush roots; LM and SEM morphological studies revealed that it is distinct from other species in the genus. Therefore, it is designated Hirschmanniella pomponiensis n. sp. Six lips are fused to form a hexagonal labial plate, six inner sensilla encircle the stoma opening, and four cephalic sensilla open in the corners of subdorsal and subventral lips. Cephalic lip region consists of six or seven annuli. The female has incomplete areolation in the lateral field, the intestine overlaps the rectum, the tail tip is pointed and without annulation. 相似文献
2.
Meloidogyne californiensis n. sp. is described and illustrated from bulrush Scirpus robustus in California. LM and SEM studies revealed that this species differs from other known species in the genus Meloidogyne especially by the prominent posterior cuticular protuberances in the female, the distinct shape of the perineal pattern which is marked by one prominent stria in the perineum, indistinct lateral lines, many broken discontinuous striae on both sides of the arch, and the excretory pore being located posterior to stylet base. Second-stage juveniles 448-628 μm long, stylet length 11-13 μm, styler delicate, with small knobs sloping posteriorly, cephalic region with 2 or 3 annuli, and inflated rectum. Males vary greatly in size (712-1,952 μm), stylet length 18-28 μm (mean 22 μm), cephalic region slightly set off the body with two or three annuli, spear heavy with massive rounded knobs, lateral field marked by four areolated incisures as seen by SEM. 相似文献
3.
Unlike many higher plants Euphorbia granulata and E. heterophylla do not encourage the development of fungi in their rhizospheres. Fungi recovered therefrom were limited both in number and range of species. The rhizosphere of E. heterophylla was slightly favourable to soil fungi when compared with the other weed plant. Aspergillus niger was least affected by both types of rhizosphere. Expressed latexcontaining sap of E. granulata was remarkably inhibitory to submerged cultures of A. flavus, A. nidulans, Fusarium sp., Curvularia sp. and Helminthosporium. Conidia and mycelial fragments recovered from these cultures failed either to germinate or resume growth thus exhibiting an antifungal property of E. granulata latex. 相似文献
4.
Pascal Hunziker Hassan Ghareeb Lena Wagenknecht Christoph Crocoll Barbara Ann Halkier Volker Lipka Alexander Schulz 《Plant, cell & environment》2020,43(6):1571-1583
Powdery mildew is a fungal disease that affects a wide range of plants and reduces crop yield worldwide. As obligate biotrophs, powdery mildew fungi manipulate living host cells to suppress defence responses and to obtain nutrients. Members of the plant order Brassicales produce indole glucosinolates that effectively protect them from attack by non-adapted fungi. Indol-3-ylmethyl glucosinolate is constitutively produced in the phloem and transported to epidermal cells for storage. Upon attack, indol-3-ylmethyl glucosinolate is activated by CYP81F2 to provide broad-spectrum defence against fungi. How de novo biosynthesis and transport contribute to defence of powdery mildew-attacked epidermal cells is unknown. Bioassays and glucosinolate analysis demonstrate that GTR glucosinolate transporters are not involved in antifungal defence. Using quantitative live-cell imaging of fluorophore-tagged markers, we show that accumulation of the glucosinolate biosynthetic enzymes CYP83B1 and SUR1 is induced in epidermal cells attacked by the non-adapted barley powdery mildew Blumeria graminis f.sp. hordei. By contrast, glucosinolate biosynthesis is attenuated during interaction with the virulent powdery mildew Golovinomyces orontii. Interestingly, SUR1 induction is delayed during the Golovinomyces orontii interaction. We conclude that epidermal de novo synthesis of indol-3-ylmethyl glucosinolate contributes to CYP81F2-mediated broad-spectrum antifungal resistance and that adapted powdery mildews may target this process. 相似文献
5.
The present study aimed to investigate the effects of different levels of dietary supplementation of grape seed extract (GSE) on growth performance, carcass traits and antioxidant status of rabbits under heat stress conditions (temperature humidity index 87.5–93.5). Weaned male New Zealand White (NZW) rabbits about 6 weeks old (n = 144, mean body weight 705 g) were randomly allotted to four dietary groups. The Control group was fed a basal diet without GSE; the experimental groups received the basal diet with 100, 200 and 300 mg GSE/kg (Groups 100 GSE, 200 GSE and 300 GSE, respectively). The experimental period lasted for 8 weeks. Compared with other groups, rabbits of Group 300 GSE had the best body weight gain and feed conversion ratio and the lowest mortality. Dietary GSE improved carcass weight, percentage of hot carcass, intestine and edible giblets, while total non-edible parts were reduced (p ≤ 0.05) in comparison with the Control group. In Groups 200 GSE and 300 GSE, plasma total protein, albumin and globulin were increased (p ≤ 0.05). In contrast, all supplementation levels of GSE reduced (p ≤ 0.05) the plasma concentrations of total lipids, total cholesterol, triglycerides and low-density lipoproteins. Antioxidant enzymes of rabbits (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase) and total antioxidant capacity in blood were increased (p ≤ 0.05) by adding dietary GSE. However, malondialdehyde was reduced (p ≤ 0.001) with increasing GSE levels. Generally, grape seeds can be considered as rich source of phenolic and flavonoid compounds. The results of the study revealed that all tested levels of GSE were useful as a natural protection against heat stress to maintain performance, carcass traits and antioxidant status and could reduce the negative effects of heat stress in rabbits. 相似文献
6.
Fourth‐derivative synchronous spectrofluorimetry and HPLC with fluorescence detection as two analytical techniques for the simultaneous determination of itopride and domperidone
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Two simple, rapid and sensitive methods, namely, fourth‐derivative synchronous spectrofluorimetry (method I) and HPLC with fluorescence detection (method II) were developed for the simultaneous analysis of a binary mixture of itopride HCl (ITP) and domperidone (DOM) without prior separation. The first method was based on measuring the fourth derivative of the synchronous fluorescence spectra of the two drugs at Δλ = 40 nm in methanol. The different experimental parameters affecting the synchronous fluorescence of the studied drugs were carefully optimized. Chromatographic separation was performed in < 6.0 min using a RP C18 column (250 mm × 4.6 mm i.d., 5 µm particle size) with fluorescence detection at 344 nm after excitation at 285 nm. A mobile phase composed of a mixture of 0.02 M phosphate buffer with acetonitrile in a ratio of 55 : 45, pH 4.5, was used at a flow rate of 1 mL/min. Linearity ranges were found to be 0.1–2 µg/mL for ITP in both methods, whereas those for DOM were found to be 0.08–2 and 0.05–1.5 µg/mL in methods I and II, respectively. The proposed methods were successfully applied for the determination of the studied drugs in synthetic mixtures and laboratory‐prepared tablets. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
Guenin L Grosjean Y Fraichard S Acebes A Baba-Aissa F Ferveur JF 《Developmental biology》2007,304(1):62-74
Adaptive animal behaviors depend upon the precise development of the nervous system that underlies them. In Drosophila melanogaster, the pan-neural prospero gene (pros), is involved in various aspects of neurogenesis including cell cycle control, axonal outgrowth, neuronal and glial cell differentiation. As these results have been generally obtained with null pros mutants inducing embryonic lethality, the role of pros during later development remains poorly known. Using several pros-Voila (prosV) alleles, that induce multiple developmental and behavioral anomalies in the larva and in adult, we explored the relationship between these phenotypes and the variation of pros expression in 5 different neural regions during pre-imaginal development. We found that the quantity of pros mRNA spliced variants and of Pros protein varied between these alleles in a tissue-specific and developmental way. Moreover, in prosV1 and prosV13 alleles, the respective decrease or increase of pros expression, affected (i) neuronal and glial cell composition, (ii) cell proliferation and death and (iii) axonal-dendritic outgrowth in a stage and cellular context dependant way. The various phenotypic consequences induced during development, related to more or less subtle differences in gene expression, indicate that Pros level needs a precise and specific adjustment in each neural organ to allow its proper function. 相似文献
8.
Nemat?M.?HassanEmail author Mamdouh?S.?Serag Fawzia?M.?El-Feky 《Acta Physiologiae Plantarum》2004,26(2):165-175
Mung bean and tomato were in vitro selected on media containing 0, 25, 50, 100 and 150 mM NaCl. Two types of media (hormone supplemented media, CB and hormone
free media, MS) were used for mung bean using cotyledon explants whereas two types of explants (cotyledons and shoot apices)
were used for tomato on MS media. Total-N, protein content, nitrite reductase (NiR) activity and protein protein profiles
were checked in selected plants and compared to original non selected ones. NaCl at low concentrations slightly increased
total-N in shoots and roots of in vitro selected mung bean and tomato whereas higher concentrations induced significant reductions. Similar increases in protein
content were detected at lower concentrations with no significant effects thereover. On the contrary, NaCl gradually inhibited
NiR activity. Similar responses of total-N, protein and NiR activity, but with greater magnitudes, were detected in original
plants. In addition, NaCl significantly reduced dry weights of shoots and roots of either in vitro selected or, in particular, original intact plants. Moreover, electrophoresis (SDS-PAGE) of protein from shoots of either
in vitro selected or intact plants showed that NaCl induced new protein bands while some others were concomitantly disappeared. The
induction of one or more of the 86.4, 79, 77.6, 77 and 71.5 kDa bands following in vitro selection and/or the disappearance of the 86 kDa band from intact plants seemed necessary for mung bean resistance. Also,
the presence of 86.2 kDa band and/or the loss of the 85.8 and 57.5 kDa bands might be included in tomato resistance. Of these
induced bands in mung bean selected on CB media, only two bands were detected in plants selected on MS media. In tomato, two
bands lost following selection from cotyledons but only one band lost following selection from shoot apices. These changes
in protein pattern therefore might serve as adaptive regulators for resistance to NaCl. 相似文献
9.
Li J French BA Fu P Bardag-Gorce F French SW 《American journal of physiology. Gastrointestinal and liver physiology》2003,285(2):G442-G448
The cause of the urinary alcohol level (UAL) cycle in rats fed ethanol at a constant rate has been shown to involve the hypothalamic-pituitary thyroid axis. Because the effect of thyroid hormone on the metabolic rate is augmented by catecholamines, the role of catecholamines was investigated by using the intragastric ethanol feeding model of alcoholic liver disease in which the UAL cycles over a 6- to 10-day period. The diet was supplemented with ephedrine and caffeine to test the hypothesis that the UAL cycle involves catecholamines. The UAL was followed to see whether the cycle was ablated by catecholamine supplements. Ethanol fed alone increased the blood levels of catecholamines significantly more than did ephedrine fed alone. However, blood catecholamine levels were significantly higher when ethanol was fed with ephedrine compared with the sum of ethanol and ephedrine fed alone. This indicated that the effect of ethanol and ephedrine were synergistic. The UAL cycle was completely ablated in the ethanol + ephedrine-fed rats. These rats tolerated a much higher dose of ethanol, indicating that they metabolized alcohol faster due to an increase in metabolic rate caused by ephedrine. In the ethanol + ephedrine-fed rats the liver pathology included significantly higher alanine amino transferase (ALT) in the blood and centrilobular ischemic necrosis in the liver. Necrosis was not present in the rats fed ephedrine alone. In conclusion, catecholamine supplements prevented the UAL cycle by increasing the metabolic rate to the point at which fluctuations in the metabolic rate caused by alcohol were prevented. 相似文献
10.
Fawzia H. Toulah Saedia A. Sayed Al-Ahl Dawlat M. Amin Mona H. Hamouda 《Saudi Journal of Biological Sciences》2011,18(2):151-156
Toxoplama gondii (Apicomplexa: Coccidia), an obligatory intracellular parasite with a unique capacity to invade virtually all nucleated cell type from warm-blooded vertebrate hosts. Despite the efficiency with which Toxoplasma enters its host cell, it remains unresolved if invasion occurs by direct penetration of the parasite or through phagocytosis. In the present work, electron microscopic study was designed to examine the entry process of Toxoplasma (RH strain) into macrophages and non phagocytic-host cells (Hela cells) and to observe the ultrastructure changes associated with intracellular parasitism. The results showed that both active invasion and phagocytosis were occurred and revealed that invasion is an ordered process that initiates with binding of the parasite at its apical end followed by tight-fitting invagination of the host cell membrane and a prominent constriction in the parasite at the site of penetration. The process ended by the professional parasitophorous vacuole that is distinct at the outset from those formed by phagocytosis in which once Toxoplasma triggered, phagocytic uptake can proceed by capture of the parasite within a loose fitting vacuole formed by localized membrane ruffling. The cytopathic effects of the parasite on macrophages and Hela cells were demonstrated within 5–15 h post-inoculation in the form of degenerative mitochondria, swelling Golgi apparatus and widening of endoplasmic reticulum indicating intracellular oedema. These changes were exaggerated and several cells were found dead after 48–72 h. 相似文献