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921.
Alshaimaa Tarek Shrouk Khalaf El-Sayed Wendy A. Woodward Mohamed El-Shinawi Jon Mark Hirshon Mona Mostafa Mohamed 《Current issues in molecular biology》2022,44(6):2730
Inflammatory breast cancer (IBC) is an aggressive phenotype with a high recurrence and low survival rate. Approximately 90% of local breast cancer recurrences occur adjacent to the same quadrant as the initial cancer, implying that tumor recurrence may be caused by residual cancer cells and/or quiescent cancer stem cells (CSCs) in the tumor. We hypothesized that wound fluid (WF) collected after modified radical mastectomy (MRM) may activate cancer cells and CSCs, promoting epithelial mesenchymal transition (EMT) and invasion. Therefore, we characterized the cytokinome of WF drained from post-MRM cavities of non-IBC and IBC patients. The WF of IBC patients showed a significantly higher expression of various cytokines than in non-IBC patients. In vitro cell culture models of non-IBC and IBC cell lines were grown in media conditioned with and/without WF for 48 h. Afterwards, we assessed cell viability, the expression of CSCs and EMT-specific genes, and tumor invasion. Genes associated with CSCs properties and EMT markers were regulated in cells seeded in media conditioned by WF. IBC-WF exhibited a greater potential for inducing IBC cell invasion than non-IBC cells. The present study demonstrates the role of the post-surgical tumor cavity in IBC recurrence and metastasis. 相似文献
922.
923.
Abdelhamid A. Hamdy Nouran A. Elattal Magdy A. Amin Amal E. Ali Nahla M. Mansour Ghada E. A. Awad Hassan M. Awad Mona A. Esawy 《World journal of microbiology & biotechnology》2017,33(4):69
Five bacterial isolates from honey and bee gut were selected based on their high levansucrase activity and levan yield which were strongly positively correlated. All isolates showed good tolerance to temperature up to 70?°C, to NaCl up to 3 M and to 0.1% H2O2. They maintained over 59 and 64% survival at pH 9.0 and 2.0 respectively, but showed varying tolerance to 0.1% bile salts and pancreatic enzymes. Most isolates were susceptible to widely used antibiotics, but demonstrated diverse antimicrobial activity. Non hemolytic isolates were identified on the basis of 16S rRNA sequencing as Bacillus subtilis HMNig-2 and B. subtilis MENO2 with 97% homology. They exhibited promising probiotic characteristics and achieved highest levansucrase activity of 94.1 and 81.5 U/mL respectively. Both exhibited highest biofilm formation ability in static microtiter plate assay. Also, they achieved 34 and 26% adhesion respectively to Caco-2cells and had highest free radical scavenging activity of 30.8 and 26.2% respectively. The levans of the two isolates showed good antimicrobial activity against some pathogens and exhibited positive prebiotic effect (prebiotic index >1) with Lactobacillus casei and Lactobacillus reuteri. Results suggest a correlation between levansucrase production, levan yield and pre-probiotic activities of the studied strains. 相似文献
924.
Paternity following multiple mating in ladybird <Emphasis Type="Italic">Harmonia axyridis</Emphasis>
Mona?Awad Lubomír?Piálek Alena?Krej?í Guillaume?Laugier Old?ich?NedvědEmail author 《BioControl》2017,62(3):297-307
We investigated factors which may determine realised paternity following multiple mating in a promiscuous ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), namely the mating order and ability of males of different morphs to fertilize females. In experiments using males of two colour morphs, we found that the first male had a reproductive advantage over the second male (sperm precedence P2 = 0.38). Males of the melanic morph spectabilis had a reproductive advantage over males of the semi-melanic morph axyridis (P2 = 0.35). Analysis of paternity using microsatellites applied to young larvae, which avoids possible differential mortality of progeny, confirmed the precedence of the first male and higher paternity rate of colour morphs that are more frequent in the wild. Hatchability of eggs increased from 65% after the first mating to 85% after the second mating delayed by five days. Average duration of mating was 157 min and did not differ between the first and second mating and between the colour morphs of males. 相似文献
925.
926.
Jennifer Rubin Grandis Arup Chakraborty Qing Zeng Mona F. Melhem David J. Tweardy 《Journal of cellular biochemistry》1998,69(1):55-62
Interruption of an autocrine growth pathway involving TGF-α and EGFR may inhibit tumor growth and improve survival in head and neck cancer patients. We previously demonstrated that biopsy specimens and established cell lines from patients with squamous cell carcinoma of the head and neck (SCCHN) overexpress TGF-α and its receptor, epidermal growth factor receptor (EGFR) at both the mRNA and protein levels. Protein localization studies showed that TGF-α and EGFR are produced by the same epithelial cells in tissues from head and neck cancer patients further supporting a role for this ligand-receptor pair in an autocrine growth pathway. To confirm that TGF-α contributes to autocrine growth, we examined the effect of down regulation of TGF-α protein on SCCHN cell proliferation. Treatment of 6 SCCHN cell lines with antisense oligodeoxynucleotides targeting the translation start site of human TGF-α mRNA decreased TGF-α protein production by up to 93% and reduced cell proliferation by a mean of 76.2% compared to a 9.7% reduction with sense oligonucleotide (range P<0R > = 0.036–0.0001). TGF-α antisense oligonucleotide exposure also decreased TGF-α protein levels in normal oropharyngeal mucosal epithelial cells, however their growth rate was not affected. These findings indicate that TGF-α is participating in an autocrine signaling pathway in transformed, but not in normal mucosal epithelial cells, that promotes proliferation. J. Cell. Biochem. 69:55–62, 1998. © 1998 Wiley-Liss, Inc. 相似文献
927.
Understanding bacterial communication mechanisms is imperative to improve our current understanding of bacterial infectivity and find alternatives to current modes of antibacterial therapeutics. Both Gram-positive and Gram-negative bacteria use quorum sensing (QS) to regulate group behaviours and associated phenotypes in a cell-density-dependent manner. Group behaviours, phenotypic expression and resultant infection and disease can largely be attributed to efficient bacterial communication. Of particular interest are the communication mechanisms of Gram-positive bacteria known as streptococci. This group has demonstrated marked resistance to traditional antibiotic treatment, resulting in increased morbidity and mortality of infected hosts and an ever-increasing burden on the healthcare system. Modulating circuits and mechanisms involved in streptococcal communication has proven to be a promising anti-virulence therapeutic approach that allows managing bacterial phenotypic response but does not affect bacterial viability. Targeting the chemical signals bacteria use for communication is a promising starting point, as manipulation of these signals can dramatically affect resultant bacterial phenotypes, minimizing associated morbidity and mortality. This review will focus on the use of modified peptide signals in modulating the development of proliferative phenotypes in different streptococcal species, specifically regarding how such modification can attenuate bacterial infectivity and aid in developing future alternative therapeutic agents. 相似文献
928.
Remodeling of the notochord during development of vertebral fusions in Atlantic salmon (Salmo salar)
Ytteborg E Torgersen JS Pedersen ME Baeverfjord G Hannesson KO Takle H 《Cell and tissue research》2010,342(3):363-376
Histological characterization of spinal fusions in Atlantic salmon (Salmo salar) has demonstrated shape alterations of vertebral body endplates, a reduced intervertebral space, and replacement of intervertebral
cells by ectopic bone. However, the significance of the notochord during the fusion process has not been addressed. We have
therefore investigated structural and cellular events in the notochord during the development of vertebral fusions. In order
to induce vertebral fusions, Atlantic salmon were exposed to elevated temperatures from fertilization until they attained
a size of 15 g. Based on results from radiography, intermediate and terminal stages of the fusion process were investigated
by immunohistochemistry and real-time quantitative polymerase chain reaction. Examination of structural extracellular matrix
proteins such as Perlecan, Aggrecan, Elastin, and Laminin revealed reduced activity and reorganization at early stages in
the pathology. Staining for elastic fibers visualized a thinner elastic membrane surrounding the notochord of developing fusions,
and immunohistochemistry for Perlecan showed that the notochordal sheath was stretched during fusion. These findings in the
outer notochord correlated with the loss of Aggrecan- and Substance-P-positive signals and the further loss of vacuoles from
the chordocytes in the central notochord. At more progressed stages of fusion, chordocytes condensed, and the expression of
Aggrecan and Substance P reappeared. The hyperdense regions seem to be of importance for the formation of notochordal tissue
into bone. Thus, the remodeling of notochord integrity by reduced elasticity, structural alterations, and cellular changes
is probably involved in the development of vertebral fusions. 相似文献
929.
930.
Thierry Poynard Dominique Thabut Mona Munteanu Vlad Ratziu Yves Benhamou Olivier Deckmyn 《PloS one》2010,5(8)