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61.
The effect of infection by Meloidogyne javanica and Heterodera trifolii on number, size, structure and efficiency of nodules formed by Rhizobiurn trifolii on white clover roots was investigated. Introduction of nematodes one week before, simultaneously, or one week following inoculation with Rhizobium bacteria did not hinder nodule formation. Nodule size did not differ between nematode-infected and nematode-free plants. Formation of nodules on M. javanica galls and gall formation on the nodules have been reported. The structure of nodular tissues was not disturbed by nematode infection, even though giant cells were formed inside the vascular bundles. The nitrogen-fixation efficiency of nematode-infected nodules was not impaired; however, earlier disintegration of nodules as a result of M. javanica infection ultimately deprived the plants of nitrogenous materials. The drastic reduction of the total-N in H. trifolii-infected plants reflected stunting of the entire plant due to nematode infection. Both nematodes invaded the entire root system, uniformly showing preference for nodules. 相似文献
62.
Butana and Kenana breeds from Sudan are part of the East African zebu Bos indicus type of cattle. Unlike other indigenous zebu cattle in Africa, they are unique due to their reputation for high milk production and are regarded as dairy cattle, the only ones of their kind on the African continent. In this study, we sequenced the complete mitochondrial DNA (mtDNA) D‐loop of 70 animals to understand the maternal genetic variation, demographic profiles and history of the two breeds in relation to the history of cattle pastoralism on the African continent. Only taurine mtDNA sequences were identified. We found very high mtDNA diversity but low level of maternal genetic structure within and between the two breeds. Bayesian coalescent‐based analysis revealed different historical and demographic profiles for the two breeds, with an earlier population expansion in the Butana vis a vis the Kenana. The maternal ancestral populations of the two breeds may have diverged prior to their introduction into the African continent, with first the arrival of the ancestral Butana population. We also reveal distinct demographic history between the two breeds with the Butana showing a decline in its effective population size (Ne) in the recent past ~590 years. Our results provide new insights on the early history of cattle pastoralism in Sudan indicative of a large ancient effective population size. 相似文献
63.
Summary The action of methanol on the stimulatory or inhibitory effect produced by certain trace elements on citric acid production by Aspergillus niger was investigated. Methanol addition masked the stimulatory action of zinc addition and also eliminated the inhibitory effect of iron and manganese. It was also remarkable that some of the trace elements masked the toxic action of methanol on both acid production and growth. 相似文献
64.
65.
We evaluated the sterilizing effect of 3-monochloropropane-1, 2-diol (3-MCPD) in male Egyptian fruit bats (Rousettus aegyptiacus). We used three groups. One was treated with 70 mg/kg 3-MCPD for 4 days. The second group was treated with 3-MCPD as a bait formulation (known concentration of 3-MCPD mixed with a known amount of food). The third group was untreated controls. We compared the weights of the reproductive organs, histology of the testes, occurrence of spermatogenesis, and the count, motility and abnormalities of epididymal sperm of treated males with those of the untreated control group. 3-MCPD caused significantly decreased weights of reproductive organs, several testicular histological alterations and spermatogenic arrest accompanied by significant decreases in sperm count and motility, and significantly increased number of abnormal sperm. 3-MCPD bait was readily accepted by the animals. 3-MCPD, even in low doses and after limited exposure, disrupted spermatogenesis in males of the Egyptian fruit bat. Our findings have potential value for public health and agricultural authorities, and for vertebrate pest managers. 3-MCPD may have application for control of this pest. 相似文献
66.
Samar Said Fatahala Shahenda Mahgub Heba Taha Rania Helmy Abd-El Hameed 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):809-817
Pyrrolopyrimidin-4-ylidene-malononitriles IIa–d were prepared as important intermediates for preparation of a new series of spiro-pyrrolopyrimidines. These intermediates undergo cyclisation via reaction with acetylacetone, guanidine hydrochloride or hydrazine hydrate. Elemental and spectroscopic evidences for the structures of these compounds are presented. The final compounds have been monitored for in vivo anti-hyperglycemic activity, compared with Amaryl as standard drug. Among 12 tested compounds, both spiro (pyrano IIIb and pyrazlo Va) derivatives exhibit promising anti-hyperglycemic activity. 相似文献
67.
Christopher E. Ramsden Marie Hennebelle Susanne Schuster Gregory S. Keyes Casey D. Johnson Irina A. Kirpich Jeff E. Dahlen Mark S. Horowitz Daisy Zamora Ariel E. Feldstein Craig J. McClain Beverly S. Muhlhausler Maria Makrides Robert A. Gibson Ameer Y. Taha 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(10):1206-1213
Background
Linoleic acid (LA) is abundant in modern industrialized diets. Oxidized LA metabolites (OXLAMs) and reactive aldehydes, such as 4-hydroxy-2-nonenal (4-HNE), are present in heated vegetable oils and can be endogenously synthesized following consumption of dietary LA. OXLAMs have been implicated in cerebellar degeneration in chicks; 4-HNE is linked to neurodegenerative conditions in mammals. It unknown whether increasing dietary LA or OXLAMs alters the levels of oxidized fatty acids (oxylipins), precursor fatty acids, or 4-HNE in mammalian brain.Objectives
To determine the effects of increases in dietary OXLAMs and dietary LA, on levels of fatty acids, oxylipins, and 4-HNE in mouse brain tissues.Methods
Mice (n?=?8 per group) were fed one of three controlled diets for 8?weeks: (1) a low LA diet, (2) a high LA diet, or (3) the low LA diet with added OXLAMs. Brain fatty acids, oxylipins, and 4-HNE were quantified in mouse cerebellum and cerebral cortex by gas chromatography-flame ionization detection, liquid chromatography-tandem mass spectrometry, and immunoblot, respectively.Results
Increasing dietary LA significantly increased omega-6 fatty acids, decreased omega-3 fatty acids, and increased OXLAMs in brain. Dietary OXLAMs had minimal effect on oxidized lipids but did decrease both omega-6 and omega-3 fatty acids. Neither dietary LA nor OXLAMs altered 4-HNE levels.Conclusion
Brain fatty acids are modulated by both dietary LA and OXLAMs, while brain OXLAMs are regulated by endogenous synthesis from LA, rather than incorporation of preformed OXLAMs. 相似文献68.
Zenna Fawzia Ghareeb Lobna S. Taha 《Journal of Genetic Engineering and Biotechnology》2018,16(2):669-675
The effect of some factors on in vitro consecutive micropropagation behavior of Antigonon leptopus was examined including those of culture establishment, shootlets multiplication, rooting and acclimatization stages. The highest percent of aseptic cultures and survival of explants (100%) were obtained as a result of using Clorox 10% for 3?min followed by MC 0.1% for 2?min while, using each of them individually (Clorox 20% or MC 0.1%) for 5?min caused the highest percent of shoot formation. During the multiplication stage, the highest percent of shoot formation was reached to 100% with repeating culture of explants (two times) on MS medium supplemented with 2ip at 1.0 and IBA at 0.2?mg/l. The highest numbers of shootlets/explant were obtained when 2.0?mg/l of BAP or 0.5?mg/l BA?+?0.2?mg/l of IBA were added to MS culture medium. Culturing the explants on MS medium supplemented with 2ip at 0.5 or 1.0?mg/l each combined with 0.2?mg/l of IBA showed the longest shootlets. Reducing the strength of culture media to ½ or ¾ had promotion effect on rooting formation of shootlets. The best results of plant acclimatization (survival percent, plant height and root length) were obtained by using sand or peat moss soil. The amplified DNA fragments using B7, B9 and C19 primers for mother and micropropagated plants showed that the produced pattern by primer B7 had a maximum number of 10 bands of DNA fragments with molecular size ranging between 1025.57 and 176.36?bp, micropropagated plants showed 95.2% similarity in relation to mother plant. 相似文献
69.
Surya Sudheer Zain Taha Sivakumar Manickam Asgar Ali Poh Guat Cheng 《Fungal biology》2018,122(5):293-301
Following the importance of antler-type fruiting bodies of Ganoderma lucidum, in this study, the impact of main growth parameters such as ventilation and light on the development of antler-type fruiting bodies has been investigated together with the determination of physico-chemical properties of antler fruiting bodies. For this, the primordia bags of G. lucidum were kept under controlled ventilation to adjust the CO2 produced by the mushrooms owing to its respiration under light and dark conditions. The bioactive compounds such as phenolics, flavonoids, water-soluble polysaccharides and ganoderic acid showed a two-fold increase in the antler-type fruiting bodies as compared to normal kidney-shaped fruiting bodies. It is assumed from this study that the antler type fruiting bodies are developed due to restricted ventilation which causes an increase in the level of CO2 gas in the air as a result of respiration of mushroom. The shape and colour of antler fruiting bodies again dependent on the light provided in the growth chamber. This study also proves that with the manipulation of light and ventilation antler-type fruiting bodies of G. lucidum could be developed with higher quantity of bioactive compounds and with higher antioxidant potential. 相似文献
70.
Serum haptoglobin concentration was determined in 102 Iraqi Awassi ewes. Blood samples were collected from 82 ewes before the correction of dystocia, 10 ewes with eutocia 2 to 4 h after parturition and 10 nonpregnant ewes during the seasonal anestrus phase. The mean serum haptoglobin concentration was significantly higher (P < 0.01) in ewes with dystocia than in ewes with normal births and in the nonpregnant ewes. No significant difference was found between serum haptoglobin concentrations of ewes with ringwomb and ewes with dystocia due to other causes. There was a significant elevation (P < 0.01) of serum haptoglobin in cases treated 24 h after labor compared with those treated during the first 24 h. Significant (P < 0.05) differences were found between serum haptoglobin concentrations in ewes treated surgically and those treated manually. 相似文献