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941.
Eiman M. Zytoon Hussein I. El-Belbasi Takeo Matsumura 《Microbiology and immunology》1993,37(5):419-421
Female Aedes albopictus mosquitoes of the Miki strain were experimentally fed on defibrinated sheep blood containing 5× 107 PFU of chikungunya virus and 20,000 microfilariae of Dirofilaria immitis per milliliter. Fully engorged mosquitoes transmitted the virus to a small percentage of the F1 progeny, but females of the F1 generation did not transmit the virus to the F2 progeny. The control mosquitoes that ingested the virus without microfilariae did not transmit the virus to their eggs, larvae, or pupae in the F1 or F2 generations. These results showed that A. albopictus of this strain that concurrently ingested the virus and microfilariae transmitted the virus by the transovarial route under experimental conditions. 相似文献
942.
The herpes simplex virus 1 (HSV-1) immediate-early protein, infected cell protein 22 (ICP22), is required for efficient replication in restrictive cells, for virus-induced chaperone-enriched (VICE) domain formation, and for normal expression of a subset of viral late proteins. Additionally, ICP22 is important for optimal acute viral replication in vivo. Previous studies have shown that the US1 gene that encodes ICP22, produces an in-frame, N-terminally truncated form of ICP22, known as US1.5. To date, studies conducted to characterize the functions of ICP22 have not separated its functions from those of US1.5. To determine the individual roles of ICP22 and US1.5, we made viral mutants that express either ICP22 with an M90A mutation in the US1.5 initiation codon (M90A) or US1.5 with three stop codons introduced upstream of the US1.5 start codon (3×stop). Our studies showed that, in contrast to M90A, 3×stop was unable to replicate efficiently in the eyes and trigeminal ganglia of mice during acute infection, to efficiently establish a latent infection, or to induce VICE domain formation and was only mildly reduced in its replication in restrictive HEL-299 cells and murine embryonic fibroblasts (MEFs). Both mutants enhanced the expression of the late viral proteins virion host shutoff (vhs) and glycoprotein C (gC) and inhibited viral gene expression mediated by HSV-1 infected cell protein 0 (ICP0). When we tested our mutants'' sensitivity to type I interferon (beta interferon [IFN-β]) in restrictive cells, we noticed that the plating of the ICP22 null (d22) and 3×stop mutants was reduced by the addition of IFN-β. Overall, our data suggest that US1.5 partially complements the functions of ICP22. 相似文献
943.
Taghibeikzadehbadr Pejman Shirian Sadegh Sabouri Mostafa 《Molecular biology reports》2020,47(12):9251-9258
Molecular Biology Reports - Muscle contraction stimulates a transient change of myogenic factors, partly related to the mode of contractions. Here, we assessed the response of IGF-1Ea, IGF-1Eb,... 相似文献
944.
Khalid K. Abed Ahmed A. Hussein Mowafaq M. Ghareeb Alaa A. Abdulrasool 《AAPS PharmSciTech》2010,11(1):356-361
Diazepam is one of the most prescribed benzodiazepines. The purpose of the present research was to optimize the formulation
of orodispersible tablets of diazepam. Orodispersible tablets of diazepam were prepared using different types of superdisintegrants
(Ac-Di-Sol, sodium starch glycolate, and crospovidone (CP)) and different types of subliming agents (camphor and ammonium
bicarbonate (AB)) at different concentrations and two methods of tablets preparations (wet granulation and direct compression
methods). The formulations were evaluated for flow properties, wetting time, hardness, friability, content uniformity, in vivo disintegration time (DT), release profiles, and buccal absorption tests. All formulations showed satisfactory mechanical
strength except formula F5 which contains camphor and formula F9 which is prepared by direct compression method. The results
revealed that the tablets containing CP as a superdisintegrant have good dissolution profile with shortest DT. The optimized
formula F7 is prepared using 10% CP as a superdisintegrant and 20% AB as a subliming agent by wet granulation method which
shows the shortest DT and good dissolution profile with acceptable stability. This study helps in revealing the effect of
formulation processing variables on tablet properties. It can be concluded that the orodispersible tablets of diazepam with
better biopharmaceutical properties than conventional tablets could be obtained using formula F7. 相似文献
945.
Mansoureh Vatanshenassan Mehdi Mohebali Bahram Kazemi Mostafa Rezaeian 《Experimental parasitology》2010,126(2):187-190
Trichomonas vaginalis is the agent of a highly prevalent sexually transmitted disease that leads to vaginitis, urethritis, ectocervicitis and has been associated with human immunodeficiency virus (HIV). Detection of T. vaginalis based on wet-mount microscopy and culture methods is insensitive and time consuming, respectively. Thus the quest for reliable PCR techniques of T. vaginalis in vaginal discharge and urine sample is more importance. In this study, 500 urine and vaginal-discharge samples were collected from women referred to Sexual Transmitted Disease Clinic of Mirzakuchakkhan Hospital in Tehran, Iran between May 2008 and March 2009. Wet-mount and culture methods were done on the vaginal discharges, and PCR assay targeting cysteine proteinase 4 (CP4) was performed on the urine samples. The present study demonstrated 16 (3.2%) of patients were infected with T. vaginalis using culture and wet-mount, whereas PCR assay using CP4 could detect 12 (2.4%) positivity. Sensitivity and specificity of urine PCR assay compared to culture were 80% (95% CI, 54-96) and 99.6% (95% CI, 98.96-100), respectively. These results indicate that using urine-based detection method for T. vaginalis may not be appropriate in women. 相似文献
946.
Houshang Dehghanzadeh Mostafa Ghaderi-Zefrehei Seyed Ziaeddin Mirhoseini Saeid Esmaeilkhaniyan Ishaku Lemu Haruna Hamed Amirpour Najafabadi 《Journal of applied genetics》2020,61(2):231-238
Information theory is a branch of mathematics that overlaps with communications, biology, and medical engineering. Entropy is a measure of uncertainty in the set of information. In this study, for each gene and its exons sets, the entropy was calculated in orders one to four. Based on the relative entropy of genes and exons, Kullback-Leibler divergence was calculated. After obtaining the Kullback-Leibler distance for genes and exons sets, the results were entered as input into 7 clustering algorithms: single, complete, average, weighted, centroid, median, and K-means. To aggregate the results of clustering, the AdaBoost algorithm was used. Finally, the results of the AdaBoost algorithm were investigated by GeneMANIA prediction server to explore the results from gene annotation point of view. All calculations were performed using the MATLAB Engineering Software (2015). Following our findings on investigating the results of genes metabolic pathways based on the gene annotations, it was revealed that our proposed clustering method yielded correct, logical, and fast results. This method at the same that had not had the disadvantages of aligning allowed the genes with actual length and content to be considered and also did not require high memory for large-length sequences. We believe that the performance of the proposed method could be used with other competitive gene clustering methods to group biologically relevant set of genes. Also, the proposed method can be seen as a predictive method for those genes bearing up weak genomic annotations. 相似文献
947.
948.
949.
Ahlam Mostafa El‐Bakry 《Acta zoologica》2011,92(1):54-61
El‐Bakry, A.M. 2011. Comparative study of the corneal epithelium in some reptiles inhabiting different environments. —Acta Zoologica (Stockholm) 92 : 54–61. The vertebrate cornea functions in either aquatic or aerial environments and in some cases in both. In terrestrial and aerial vertebrates, the cornea contributes most of the refractive powers of the eye because of the large variation in refractive index between the air and the cornea. The present study aimed to examine and compare the main features of the corneal epithelial surface of three reptilian species related to three different families (Caretta caretta, Varanus griseus and Mabuya quinquetaeniata) and inhabiting different environment, by light, scanning (SEM) and transmission electron microscopy. The mean epithelial cell densities of the species of the study were 8.670 ± 3.134, 5.945 ± 2.144 and 2.124 ± 713 respectively. The corneal epithelium of the three species observed by SEM showed a similarity to one another indicating that the apical cell surfaces possess regular polygonal cells with varieties of microprocesses. These microprocesses were represented by microplicae, numerous microvilli and some long microridges in C. caretta, microplicae and minute microholes in V. griseus and microplicae intermingled with short microvilli in M. quinquetaeniata. According to the densities of these microprocesses, three polymorphic cell types (light, medium and dark) appeared in C. caretta, light and medium cell types were observed in V. griseus and medium and dark cell types were noticed in M. quinquetaeniata. Different types of tight adhesions were observed by transmission electron microscopy between the cell borders of the epithelial cells which differ according to environment where the species occupy. In conclusion, variation in the structure of the corneal epithelial cells appears to be related to the living environment, such as aerial, terrestrial and aquatic ones, which is occupied by every species. 相似文献
950.
Kamel Ahmed Hussein Tartoura 《Acta Physiologiae Plantarum》2001,23(2):149-156
Endogenous levels of free and conjugated IAA, auxin protectors (Prs) and peroxidase (PER) activity and their relation to adventitious
root initiation (ARI) were investigated at the potential sites of adventitious rooting in relation to exogenous application
of 250 μM ABA during the first 120 h after treatment. Cuttings from 7-day-old mung bean [Vigna radiata (L.) Wilcz.] seedlings were treated with 125, 250, and 500 μM ABA for 24 h. ABA significantly stimulated ARI but extremely
inhibited epicotyl growth as compared to control. Free and conjugated IAA were measured by reversed-phase high performance
liquid chromatography while Prs and PER activities were measured spectrophotometrically. The present results also indicate
that endogenous free IAA levels peaked later in ABA-treated cuttings than that in control, suggesting that ABA extended the
length of the induction phase of rooting process in treated cuttings and that might explain the significant delay of the appearance
of roots at the treated cuttings. Higher level of IAA conjugates was found in ABA-treated cuttings than that in untreated
ones. Pr level also peaked later in ABA-treated cuttings than that in control, indicating that ABA extended the period of
Pr activity. An initial temporary decrease of PER activity was found in associating with high levels of free IAA and Prs during
most of the primary events, while the opposite occurred during the secondary events of adventitious rooting process in both
treated and untreated cuttings. Thus, ABA may stimulate ARI in mung bean Vigna radiata cuttings by regulating the concentration and /or activities of endogenous IAA, Prs, and PER activity in favor of inducing
a large number of adventitious roots at their potential sites of adventitious rooting. 相似文献