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1.
A case of sacrococcygeal chordoma with anaplastic features is presented. The diagnosis of the anaplastic component was first established by fine needle aspiration (FNA) biopsy, which demonstrated the sarcomatous elements as well as the physaliferous cells characteristic of chordoma. Subsequent histologic examination confirmed these findings. While the FNA cytologic findings of chordoma have been previously reported, this is the first case of an anaplastic chordoma diagnosed by FNA biopsy. The embryologic origin of this unusual tumor and its differential diagnosis are discussed. 相似文献
2.
A 61-year-old male native of Mexico presented with generalized enlargement of lymph nodes. Fine needle aspiration (FNA) biopsy established lepromatous leprosy as the cause of the lymphadenopathy. The cytologic findings included abundant, frequently multinucleated histiocytes (globus cells), the cytoplasm of which showed multiple vacuoles; cytoplasmic membrane-bound vacuoles were seen free in the background. The vacuoles contained large numbers of acid-fast bacilli. Globus cells, while characteristic, are not specific for Mycobacterium leprae infection and are seen in certain atypical mycobacterioses in immunodeficient patients. This appears to be the first report of lymphadenopathy due to lepromatous leprosy in which the diagnosis was made by FNA biopsy. The immunologic spectrum of leprosy is correlated with clinical and pathologic findings, and the need to remember infectious processes in evaluating lymphadenopathy and the value of reserving air-dried and alcohol-fixed smears for special stains are emphasized. 相似文献
3.
Fine needle aspiration biopsies of tumors can yield a variety of spindle cells derived from several types of neoplasms. Among these is a rare lesion known as a "spindle-cell carcinoma" or "pseudosarcoma," which may represent a transformation of a preexisting squamous-cell carcinoma that has been subjected to radiotherapy or solar damage. The cytologic, histologic and ultrastructural features of a case of metastatic spindle-cell carcinoma of the rib subjected to fine needle aspiration are presented, and other spindle-cell tumors that should be considered in the differential diagnosis are discussed. 相似文献
4.
5.
Dr. Sherif M. H. Sanad Alshimaa A. M. Abdelsalam Aya A. Gamal Eldin Esraa H. Abdelfattah Fatma R. M. Hussein Nada G. Mohammed Nariman A. S. Taha Prof. Dr. Ahmed E. M. Mekky 《化学与生物多样性》2023,20(6):e202300546
An efficient protocol was adopted to efficiently prepare three new series of bis(pyrazolo[1,5-a]pyrimidines) linked to different spacers. The new bis(pyrazolo[1,5-a]pyrimidines) were prepared in 80–90 % yields by reacting the respective bis(enaminones) and 4-(4-substituted benzyl)-1H-pyrazole-3,5-diamines in pyridine at reflux temperature for 5–7 h. The new products showed a wide spectrum of antibacterial activity against six different bacterial strains. In general, propane- and butane-linked bis(pyrazolo[1,5-a]pyrimidines), which are attached to 3-(4-methyl- or 4-methoxybenzyl) units, had the best antibacterial activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values up to 2.5 and 5.1 μM, respectively. Additionally, the previous products demonstrated promising MurB inhibitory activity with IC50 values up to 7.2 μM. 相似文献
6.
M M Kader G Kamel M T Aziz M M Kenawy M M el-Sadani A Erfan K R Madwar N Sherif 《Acta biologica et medica Germanica》1975,34(9):1465-1469
Different blood lipid components were evaluated in obese and normal Egyptians. In obese, plasma levels of total lipoproteins, beta-lipoprotein, total cholesterol, triglycerides, and non-esterified fatty acids were found to be significantly elevated. The plasma levels of esterified cholesterol and phospholipids were found to be significantly reduced. Tertroxine caused a drop of the plasma level of total lipoproteins, beta lipoproteins and total cholesterol and rise of plasma level of non-esterified fatty acids. 相似文献
7.
Liqun Zhang Brian Button Sherif E. Gabriel Susan Burkett Yu Yan Mario H. Skiadopoulos Yan Li Dang Leatrice N. Vogel Tristan McKay April Mengos Richard C. Boucher Peter L. Collins Raymond J. Pickles 《PLoS biology》2009,7(7)
Dysfunction of CFTR in cystic fibrosis (CF) airway epithelium perturbs the normal regulation of ion transport, leading to a reduced volume of airway surface liquid (ASL), mucus dehydration, decreased mucus transport, and mucus plugging of the airways. CFTR is normally expressed in ciliated epithelial cells of the surface and submucosal gland ductal epithelium and submucosal gland acinar cells. Critical questions for the development of gene transfer strategies for CF airway disease are what airway regions require CFTR function and how many epithelial cells require CFTR expression to restore normal ASL volume regulation and mucus transport to CF airway epithelium? An in vitro model of human CF ciliated surface airway epithelium (CF HAE) was used to test whether a human parainfluenza virus (PIV) vector engineered to express CFTR (PIVCFTR) could deliver sufficient CFTR to CF HAE to restore mucus transport, thus correcting the CF phenotype. PIVCFTR delivered CFTR to >60% of airway surface epithelial cells and expressed CFTR protein in CF HAE approximately 100-fold over endogenous levels in non-CF HAE. This efficiency of CFTR delivery fully corrected the basic bioelectric defects of Cl− and Na+ epithelial ion transport and restored ASL volume regulation and mucus transport to levels approaching those of non-CF HAE. To determine the numbers of CF HAE surface epithelial cells required to express CFTR for restoration of mucus transport to normal levels, different amounts of PIVCFTR were used to express CFTR in 3%–65% of the surface epithelial cells of CF HAE and correlated to increasing ASL volumes and mucus transport rates. These data demonstrate for the first time, to our knowledge, that restoration of normal mucus transport rates in CF HAE was achieved after CFTR delivery to 25% of surface epithelial cells. In vivo experimentation in appropriate models will be required to determine what level of mucus transport will afford clinical benefit to CF patients, but we predict that a future goal for corrective gene transfer to the CF human airways in vivo would attempt to target at least 25% of surface epithelial cells to achieve mucus transport rates comparable to those in non-CF airways. 相似文献
8.
Strategies for identifying genetic risk factors in complex diseases by association studies require the comparison of allele frequencies of numerous SNPs between affected and control populations. Theoretically, hundreds of thousands of SNP markers across the genome will have to be genotyped in these studies. Genotyping SNPs one sample at a time is extremely costly and time consuming. To streamline whole genome association studies, some have proposed to screen SNPs by pooling the DNA samples initially for allele frequency determination and perform individual genotyping only when there is a significant discrepancy in allele frequencies between the affected and control populations. Here we describe a new method for determining the allele frequency of SNPs in pooled DNA samples using a two-color primer extension assay with real-time monitoring of fluorescence polarization (named kinetic FP-TDI assay). By comparing the ratio of the rate of incorporation of the two allele-specific dye-terminators, one can calculate the relative amounts of each allele in the pooled sample. The accuracy of allele frequency determination with pooled samples is within 3.3 +/- 0.8% of that determined by genotyping individual samples that make up the pool. 相似文献
9.
Gabrielle Deschamps-Francoeur Sonia Couture Sherif Abou-Elela Michelle
S Scott 《Nucleic acids research》2022,50(11):6067
Box C/D small nucleolar RNAs (snoRNAs) are a conserved class of RNA known for their role in guiding ribosomal RNA 2′-O-ribose methylation. Recently, C/D snoRNAs were also implicated in regulating the expression of non-ribosomal genes through different modes of binding. Large scale RNA–RNA interaction datasets detect many snoRNAs binding messenger RNA, but are limited by specific experimental conditions. To enable a more comprehensive study of C/D snoRNA interactions, we created snoGloBe, a human C/D snoRNA interaction predictor based on a gradient boosting classifier. SnoGloBe considers the target type, position and sequence of the interactions, enabling it to outperform existing predictors. Interestingly, for specific snoRNAs, snoGloBe identifies strong enrichment of interactions near gene expression regulatory elements including splice sites. Abundance and splicing of predicted targets were altered upon the knockdown of their associated snoRNA. Strikingly, the predicted snoRNA interactions often overlap with the binding sites of functionally related RNA binding proteins, reinforcing their role in gene expression regulation. SnoGloBe is also an excellent tool for discovering viral RNA targets, as shown by its capacity to identify snoRNAs targeting the heavily methylated SARS-CoV-2 RNA. Overall, snoGloBe is capable of identifying experimentally validated binding sites and predicting novel sites with shared regulatory function. 相似文献
10.
Hassan A. Hemeg Ihab M. Moussa Sherin Ibrahim Turki M. Dawoud Jwaher H. Alhaji Ayman S. Mubarak Saleh A. Kabli Roua A. Alsubki Azza M. Tawfik Sherif A. Marouf 《Saudi Journal of Biological Sciences》2020,27(12):3221-3227
This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). 相似文献