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1.
A Flow Cytometric method for the evaluation of the phagocytic capacity of bovine blood neutrophils is described. The neutrophils were isolated from bovine blood by a one step discontinuous gradient of Percoll. By this technique of isolation, 90 ± 2.8 % (mean ± s) of the granulocytes in the whole blood were recovered. Isolated neutrophils were incubated with FITC labeled S. aureus or zymosan particles in a ratio of 1:20 and 1:10, respectively, and a final serum concentration of 10 %. Phagocytosis was terminated after 15 min and the number of extracellular bacteria or zymosan particles and the percentage of phagocytic granulocytes were registered by Flow Cytometry (FCM). FCM and microscopic studies revealed that eosinophils play a minor role in the phagocytosis of bacteria. The neutrophils were the main population of the granulocytes which were actively phagocytic. Variation among cows in the ability of their blood neutrophils to phagocytize bacteria was evident. 相似文献
2.
Peter Mullany Chris L. Clayton Mark J. Pallen Rhona Slone Alaa Al-Saleh Soad Tabaqchali 《FEMS microbiology letters》1994,124(1):61-67
Abstract Screening of a Clostridium difficile ψEMBL3 gene library with antisera raised against C. difficile culture supernatant identified several clones expressing a 31-kDa protein. A 1.8-kb Hin dIII fragment subcloned from one of the clones was sufficient for expression of the 31-kDa polypeptide. Southern blot analysis showed a region homologous to this fragment to be present in all of 13 different C. difficile strains tested. Sequence analysis of the 1.8-kb fragment revealed three adjacent open reading frames. A database search showed that these three open reading frames appeared to encode homologues of three consecutive enzymes in the butanol/butyrate-producing pathway of Clostridium acetobutylicum (crotonase, β-hydroxybutyryl coenzyme A dehydrogenase and thiolase). 相似文献
3.
Ahmed Gamal El-Din Fahmy 《Vegetation History and Archaeobotany》1997,6(4):241-247
Macrofossils of weeds retrieved from archaeological sediments in Egypt are discussed in terms of their presence, preservation and representation significance. The study reveals 112 field weeds from 61 archaeological sites dating from Predynastic times (4500 B.C.) up to the Graeco-Roman period (A.D. 395). Most of the remains were preserved by desiccation. The 112 listed species include 24 taxa from Predynastic Hierakonpolis (3800–3500 B.C.) identified for the first time. This study is based on a selection of 97 species from the entire list. Interpretation of field weed finds from the archaeological contexts is discussed. The highest number of species, 63, is recorded from the Pharaonic period. The Predynastic era is represented by 46 species and the Graeco-Roman period by 34. The intensive archaeological excavation of Pharaonic settlements may explain the rich flora of that period compared with the two others. Floristic analysis shows that 57 species were introduced in association with crops from the Middle East and 40 may belong to the native vegetation of the Nile valley. 相似文献
4.
A series of aroyl- and aryl-hydrazide derivatives was prepared from d-glycero-d-gulo-heptono-1,4-lactone (1). The reactivity of the NH proton in these hydrazides, in terms of their dissociation constants (pKa), was determined from their electronic spectra, and correlated to the Hammett σ values of the substituents. Comparable reactivities of the NH protons for the compounds, and the effect of the substituent, were studied by n.m.r. spectroscopy. Decomposition of the aroylhydrazides with copper(II) sulfate or nitrous acid resulted in the regeneration of 1. 相似文献
5.
Recognition of gluconeogenic enzymes; Icl1, Fbp1, and Mdh2 by Gid4 ligase: A molecular docking study
The pro/N‐degron pathway is an evolved protein degradation pathway through the ubiquitin‐proteasome system. It is a vital pathway to attain protein homeostasis inside the liver cells with varying glucose levels. N‐terminal proline exists in more than 300 proteins in Saccharomyces cerevisiae, but only three of them are the gluconeogenic enzymes; isocitrate lyase (Icl1), fructose‐1,6‐bisphosphatase (Fbp1), and malate dehydrogenase (Mdh2). The present in silico study aims to structurally illustrate the binding of Icl1 enzyme to Gid4 ligase concerning its peers; Fbp1 and Mdh2. Based on the molecular docking scores and interactions, one can attribute the binding stability of Gid4 with degrons, to peptides of length six up to eight from the N‐terminal. Moreover, the percent change in the docking score provides a rationale for the unique Gid4‐Icl11‐4 interaction. The present study provides insights on the binding attitude of Gid4 ligase to degrons of different lengths, so one will consider in designing peptidomimetics to target Gid4 ligase. 相似文献
6.
7.
Afrah F. Alkhuriji Seham G. Alsaiari Suliman Y. Alomar Alaa A. Alnafjan Hussah Alobaid Manal F. El-Khadragy 《Bioscience reports》2021,41(3)
Colon cancer is one of the most common causes of deaths by cancer worldwide. Stem cells have immunosuppressive properties that promote tumor targeting and circumvent obstacles currently in gene therapy. Bone marrow stem cells are believed to have anticancer potential. The transplantation of mesenchymal stem cells (MSCs), a type of bone marrow stem cells, has been considered a potential therapy for patients with solid tumors due to their capability to enhance the immune response; MSC transplantation has received renewed interest in recent years. The present study aimed to evaluate the antiapoptotic effects of the MSCs on 1,2-dimethylhydrazine (DMH)-induced inflammation in the rat model of colorectal cancer. The rats were randomly allocated into four groups: control, treated with MSCs, induced by DMH, and induced by DMH and treated with MSCs. The MSCs were intra-rectally injected, and DMH was subcutaneously injected at 20 mg/kg body weight once a week for 15 weeks. The administration of MSCs into rats starting from day 0 of the DMH injection was found to enhance the histopathological picture. The MSC treatment resulted in fewer inflammatory cells than in the DMH group. Therefore, our findings suggest that BMCs have antitumor effects by modulating the cellular redox status and down-regulating the pro-inflammatory genes. Thus, BMCs may provide therapeutic value for colon cancer treatment. 相似文献
8.
Mohammed A. E. Sallam Leroy B. Townsend 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1215-1229
Abstract Treatment of 4-(D-gluco-pentitol-l-y1)-2-pheny1–2H-1,2,3-triazole (1) with p-toluenesulfonyl chloride in pyridine solution, afforded the homo-C-nucleoside analog, 4-(2,5-anhydro-D-gluco-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole (2) as well as its partial p-toluenesulfonyl derivative (3). 4-(5-Chloro-5-deoxy-D-gluco-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole (8), was isolated as a byproduct from the reaction. The structure and anomeric configuration of 2 was determined by acylation, 1H, 13C NMR, and NOE, spectroscopy as well as mass spectrometry. 相似文献
9.
Adel M. Attia Morsala A. Sallam Ahmed A. Almehdi Mohammed M. Abbasi 《Nucleosides, nucleotides & nucleic acids》2013,32(10):2307-2315
Abstract N3 -β-D-glucopyranosyl, galactopyranosyl and xylopyranosyl 6-methyl-2-methylthiouracil and their 5-bromo derivatives have been synthesized by coupling an a-acetobromosugar with the corresponding thiouracil. The new modified thiouridine analogues were evaluated for their inhibitory activity against Human Immunodeficiency Virus (HIV) replication in MT-4 cells as well as for their cytotoxicity. 相似文献
10.
Farsenyl pyrophosphate synthase is a potential molecular drug target of risedronate in Babesia bovis
Akio Ueno Mohamad Alaa Terkawi Miki Yokoyama Shinuo Cao Gabriel Aboge Mahmoud Aboulaila Yoshifumi Nishikawa Xuenan Xuan Naoaki Yokoyama Ikuo Igarashi 《Parasitology international》2013,62(2):189-192
A cDNA encoding farnesyl pyrophosphate synthase of Babesia bovis (BbFPPS) has been isolated, cloned and characterized as molecular drug target. Sequence analysis revealed that BbFPPS contains an open reading frame of 1011 bp with predicted 336 amino acids and molecular mass of 38 kDa. Antiserum raised in mice against recombinant BbFPPS expressed in Escherichia coli specifically reacted with native protein of B. bovis parasites by Western blot analysis and indirect immunofluorescent test. Enzymatic assay using recombinant BbFPPS revealed that the Km value of the enzyme for isopentenyl pyrophosphate and dimethylallyl pyrophosphate was 2.494 ± 1.536 μM. Risedronate inhibited the activity of BbFPPS yielding IC50 value of 8.4 ± 1.2 nM. Furthermore, the in vitro growth of B. bovis was significantly inhibited in the presence of a micromolar concentration of risedronate (IC50 = 4.02 ± 0.91 μM). No regrowth of B. bovis was observed at 10 μM of risedronate in the subsequent viability test. These results demonstrate that BbFPPS is the molecular target of risedronate, which could inhibit the in vitro growth of B. bovis. 相似文献