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71.
Attraction of Ditylenchus dipsaci and Pratylenchus penetrans to a temperature gradient was tested. Heating wires, infrared radiations and germinating alfalfa seeds were used to create a temperature gradient as small as 0.033 C/cm in agar. P. penetrans, D. dipsaci, and Tylenchorhynchus claytoni responded to a temperature gradient of 0.033 C over a 4-cm distance from the heat source. Trichodorus christiei and Xiphinema arnericanum showed no response. Individuals of P. penetrans oriented their heads towards the heat source and moved directly towards it from a 1-cm distance within 10 rain. When the heat was turned off the nematodes dispersed, but when the heat was turned on again, they reassembled. Heat from germinating alfalfa seeds, in the absence of CO₂, attracted P. penetrans. Carbon dioxide emanating from germinating alfalfa seeds failed to attract them in the absence of heat, even after 24 hr. 相似文献
72.
Ezzat K Andaloussi SE Zaghloul EM Lehto T Lindberg S Moreno PM Viola JR Magdy T Abdo R Guterstam P Sillard R Hammond SM Wood MJ Arzumanov AA Gait MJ Smith CI Hällbrink M Langel Ü 《Nucleic acids research》2011,39(12):5284-5298
Numerous human genetic diseases are caused by mutations that give rise to aberrant alternative splicing. Recently, several of these debilitating disorders have been shown to be amenable for splice-correcting oligonucleotides (SCOs) that modify splicing patterns and restore the phenotype in experimental models. However, translational approaches are required to transform SCOs into usable drug products. In this study, we present a new cell-penetrating peptide, PepFect14 (PF14), which efficiently delivers SCOs to different cell models including HeLa pLuc705 and mdx mouse myotubes; a cell culture model of Duchenne's muscular dystrophy (DMD). Non-covalent PF14-SCO nanocomplexes induce splice-correction at rates higher than the commercially available lipid-based vector Lipofectamine 2000 (LF2000) and remain active in the presence of serum. Furthermore, we demonstrate the feasibility of incorporating this delivery system into solid formulations that could be suitable for several therapeutic applications. Solid dispersion technique is utilized and the formed solid formulations are as active as the freshly prepared nanocomplexes in solution even when stored at an elevated temperatures for several weeks. In contrast, LF2000 drastically loses activity after being subjected to same procedure. This shows that using PF14 is a very promising translational approach for the delivery of SCOs in different pharmaceutical forms. 相似文献
73.
Farag A Ebrahim H ElMazoudy R Kadous E 《Birth defects research. Part B, Developmental and reproductive toxicology》2011,92(2):122-130
This study investigated the developmental toxicity of carbendazim during the organogenesis period in mice. Mated CD-1 mice were administered carbendazim at dose levels 0, 150, 300, and 600 mg/kg/day by gavage. Body weights, weight gains, and feed consumption were significantly reduced in mice administered with 300 and 600 mg/kg/day. Carbendazim exposure increased maternal levels of cholesterol, triglyceride, glucose, protein, and creatinine; and reduced the levels of estradiol and progesterone in the 300- and 600-mg/kg/day groups. In addition, exposure to carbendazim significantly reduced the number of live fetuses and increased the number of dead and resorptions at the same dose levels. External, visceral, and skeleton malformations were observed in the 300- and 600-mg/kg/day. In conclusion, exposure of pregnant mice to carbendazim induced maternal and developmental toxicity at 300 and 600 mg/kg/day. 150 mg/kg/day carbendazim produced a very slight increase in postimplantation loss, which was within the range of historical controls, and no evidence of maternal toxicity. 相似文献
74.
Propolis ethanolic extract (PEE) at 3 and 4 g/L and ultragriseofulvin (UG) at 0.75 and 1 g/L reduced the percentage of conidia
germination in twoAspergillus flavus isolates. PEE at 1–4 g/L decreased the mycelial dry mass ofA. flavus isolates by 11–80%, and aflatoxin B1 production by 34–100%. UG concentrations of 0.25–1 g/L reduced the growth and aflatoxin B1 production of the isolates by 16–88 and 48–98%, respectively. Any increase in PEE and UG concentration was accompanied by
a clear decrease in the per cent conidia germination, growth and aflatoxin B1 production. At equal concentration, UG was about 4-times more effective than PEE. 相似文献
75.
Zahran Eman Maher Abdelmohsen Usama Ramadan Khalil Hany Ezzat Desoukey Samar Yehia Fouad Mostafa Ahmed Kamel Mohamed Salah 《Phytochemistry Reviews》2020,19(4):907-953
Phytochemistry Reviews - Ocimum, commonly known as Tulsi, is a huge genus within family Lamiaceae, comprising about 64 species of annual to perennial aromatic medicinal herbs with a long history of... 相似文献
76.
77.
Elham Pishavar Fatemeh Oroojalian Zahra Salmasi Ezzat Hashemi Maryam Hashemi 《Biotechnology progress》2021,37(4):e3174
Stem cells can be used to repair dysfunctional and injured (or cancerous) tissues by delivering therapeutics. However, in comparison with other cells, it is harder to transfect drugs or genes into stem cells. Dendrimers have been considered as efficient vectors to deliver both genes and drugs to stem cells due to their unique properties including adjustable molecular weight and size, low toxicity, high loading capacity, and having multiple peripheral chemical agents which can be functionalized to improve deliverance efficiency. In this review, we discuss dendrimer-mediated drug and gene delivery to stem cells as cellular vehicles and the role of this strategy in treating a variety of disorders via regenerative medicine approaches. 相似文献
78.
Organization of human papillomavirus productive cycle during neoplastic progression provides a basis for selection of diagnostic markers 总被引:9,自引:0,他引:9 下载免费PDF全文
Middleton K Peh W Southern S Griffin H Sotlar K Nakahara T El-Sherif A Morris L Seth R Hibma M Jenkins D Lambert P Coleman N Doorbar J 《Journal of virology》2003,77(19):10186-10201
The productive cycle of human papillomaviruses (HPVs) can be divided into discrete phases. Cell proliferation and episomal maintenance in the lower epithelial layers are followed by genome amplification and the expression of capsid proteins. These events, which occur in all productive infections, can be distinguished by using antibodies to viral gene products or to surrogate markers of their expression. Here we have compared precancerous lesions caused by HPV type 16 (HPV16) with lesions caused by HPV types that are not generally associated with human cancer. These include HPV2 and HPV11, which are related to HPV16 (supergroup A), as well as HPV1 and HPV65, which are evolutionarily divergent (supergroups E and B). HPV16-induced low-grade squamous intraepithelial lesions (CIN1) are productive infections which resemble those caused by other HPV types. During progression to cancer, however, the activation of late events is delayed, and the thickness of the proliferative compartment is progressively increased. In many HPV16-induced high-grade squamous intraepithelial lesions (CIN3), late events are restricted to small areas close to the epithelial surface. Such heterogeneity in the organization of the productive cycle was seen only in lesions caused by HPV16 and was not apparent when lesions caused by other HPV types were compared. By contrast, the order in which events in the productive cycle were initiated was invariant and did not depend on the infecting HPV type or the severity of disease. The distribution of viral gene products in the infected cervix depends on the extent to which the virus can complete its productive cycle, which in turn reflects the severity of cervical neoplasia. It appears from our work that the presence of such proteins in cells at the epithelial surface allows the severity of the underlying disease to be predicted and that markers of viral gene expression may improve cervical screening. 相似文献
79.
Several molecular aberrations have been implicated in the pathogenesis of pituitary tumors, but few have proven thus far to be of therapeutic value. Pituitary tumor-derived fibroblast growth factor receptor-4 (ptd-FGFR4) is an alternatively transcribed cytoplasmic isoform lacking most of the extracellular domain. This oncogene recapitulates the morphological features of human pituitary tumors in transgenic mice. To investigate the therapeutic potential of targeting ptd-FGFR4, we examined the impact of FGFR4 tyrosine kinase inhibition in xenografted mice. GH4 pituitary cells expressing ptd-FGFR4 develop into invasive tumors. Systemic treatment of mice bearing ptd-FGFR4 tumors with the FGFR-selective inhibitor PD173074 resulted in recovery of membranous N-cadherin staining and a significant reduction in tumor volume with less invasive growth behavior. Mutation of tyrosine Y754F in ptd-FGFR4 abrogated the effect of PD173074-mediated inhibition. The pivotal role of N-cadherin as a mediator of this pituitary cell growth was demonstrated by small interfering RNA mediated down-regulation, which promoted invasive growth in xenografted mice. To validate this model in primary human pituitary tumors, we examined the expression of ptd-FGFR4, N-cadherin, and clinical behavior. Loss of membranous N-cadherin correlated with cytoplasmic FGFR4 expression and with tumor invasiveness in surgically resected human pituitary tumors. Primary human pituitary tumor cells treated with PD173074 showed restoration of N-cadherin to the membrane with dephosphorylation of retinoblastoma protein. These data highlight the pathogenetic significance of N-cadherin misexpression and emphasize the importance of FGFR partnership in mediating its functions. 相似文献
80.
A simple and green chemistry procedure for the synthesis of dihydropyrimidinones using heteropoly acid mediated cyclocondensation reaction is described. This method provides an efficient and much improved modification of the original Biginelli reaction reported in 1893, in terms of high yields, and short reaction times. It has the ability to allow a wide variety of substitutions in all three components. 相似文献