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Sak, a murine protein-serine/threonine kinase that is related to the Drosophila polo kinase and involved in cell proliferation. 总被引:5,自引:0,他引:5 下载免费PDF全文
C Fode B Motro S Yousefi M Heffernan J W Dennis 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(14):6388-6392
We have isolated murine cDNAs encoding two isoforms of a putative protein-serine/threonine kinase, designated Sak-a and Sak-b, which differ in their noncatalytic C-terminal ends. The kinase domain of Sak is related to the catalytic domains of the Drosophila polo, Saccharomyces cerevisiae CDC5, and murine Snk and Plk kinases, a family of proteins for which a role in controlling cell proliferation has been established (polo, CDC5) or implicated (Snk, Plk). Northern and in situ RNA analyses of Sak gene expression in mouse embryos and adult tissues revealed that expression was associated with mitotic and meiotic cell division. In addition, during embryogenesis, Sak expression was prominent in the respiratory and olfactory mucosa. The pattern of Sak expression and its sequence homology with the polo gene family suggest that the Sak kinase may play a role in cell proliferation. In support of this, cell growth was suppressed by expression of a Sak-a-antisense fragment in CHO cells. 相似文献
3.
Simon D Vassina E Yousefi S Kozlowski E Braathen LR Simon HU 《The Journal of allergy and clinical immunology》2004,114(4):887-895
BACKGROUND: In several clinical studies, topical calcineurin inhibitors have been shown to be effective in the treatment of atopic dermatitis (AD). They target signaling pathways that control gene expression, particularly the expression of cytokines. OBJECTIVE: We examined the cellular infiltrate in skin lesions of 10 patients with AD and characterized the cytokine pattern expressed by the infiltrating cells before and after short-term topical therapy with tacrolimus 1% ointment. METHODS: Skin biopsies were examined for histologic alterations (hematoxylin and eosin staining), composition of the cellular inflammatory infiltrate (immunofluorescence), and cytokine expression (ribonuclease protection assay, ELISA, immunofluorescence) before as well as 1 and 3 weeks after initiation of tacrolimus therapy. For comparison, biopsies from nonlesional AD and normal skin were analyzed. Systemic immunologic effects were assessed by analyzing peripheral blood leukocytes (immunofluorescence) as well as in vitro stimulated pan-T-cell cytokine production (ELISA). RESULTS: All patients showed a significant improvement of their skin lesions associated with a marked regression of spongiosis, acanthosis, and density of the cellular infiltrate in the dermis. The last was a result of reduced infiltration of T cells, B cells, and eosinophils. In contrast, the numbers of mast cells did not change. Moreover, the expression of the T H 2 cytokines IL-5, IL-10, and IL-13 in CD4 + T cells was reduced after therapy. Interestingly, tacrolimus therapy was also associated with a reduction of CD8 + T cells expressing the T H 1 cytokine IFN-gamma. Furthermore, the numbers of epidermal CD1a + dendritic cells increased after treatment. In the peripheral blood, a decrease of granulocytes (eosinophils and neutrophils) but no changes in the distribution of lymphocyte subpopulations were noticed. CONCLUSION: Topical tacrolimus treatment has anti-inflammatory effects on AD skin as indicated by reduced infiltration of cytokine expressing inflammatory cells. No evidence for drug-induced systemic immunosuppression was obtained. 相似文献
4.
Chromium (Cr) and nickel (Ni) are widely used industrial chemicals. Welders in India are inclined to possible occupational Cr and Ni exposure. The carcinogenic potential of metals is a major issue in defining human health risk from exposure. Hence, in the present investigation, 102 welders and an equal number of control subjects were monitored for DNA damage in blood leucocytes utilizing the Comet assay. The two groups had similar mean ages and smoking prevalences. A few subjects were randomly selected for estimation of Cr and Ni content in whole blood by inductively coupled plasma mass spectrometry. The Comet assay was carried out to quantify basal DNA damage. The mean comet tail length was used to measure DNA damage. Welders had higher Cr and Ni content when compared with controls (Cr, 151.65 versus 17.86 micro g/l; Ni 132.39 versus 16.91 micro g/l; P < 0.001). The results indicated that the welders had a larger mean comet tail length than that of the controls (mean +/- SD, 23.05 +/- 3.86 versus 8.94 +/- 3.16; P < 0.001). In addition, the micronucleus test on buccal epithelial cells was carried out in a few randomly selected subjects. Welders showed a significant increase in micronucleated cells compared with controls (1.30 versus 0.32; P < 0.001). Analysis of variance revealed that occupational exposure (P < 0.05) had a significant effect on DNA mean tail length, whereas smoking and age had no significant effect on DNA damage. The current study suggested that chronic occupational exposure to Cr and Ni during welding could lead to increased levels of DNA damage. 相似文献
5.
Fahimeh Akbarian Marziyeh Tavalaee Roya Sherkat Mohammad Shahrooei Mohammad Hossein Nasr-Esfahani 《Andrologia》2021,53(7):e14080
Primary ciliary dyskinesia (PCD) is a disorder of structure and function of motor ciliary and dyskinetic activity of ciliary in the fallopian tubes of affected women and could lead to infertility in some cases. In vitro fertilisation (IVF) is a choice of treatment in infertile women with PCD, which could conquer the tubal dysfunction. In this case study, we report a PCD affected woman with infertility who was treated by IVF and pregnancy was achieved but it failed due to the spontaneous abortion. We also performed whole-exome sequencing for this case and her PCD-affected sister, which did not reveal any genetic abnormality related to the PCD or infertility. 相似文献
6.
Habib Sadeghirad Tayyeb Bahrami Sepideh M. Layeghi Hassan Yousefi Meysam Rezaei Seyed R. Hosseini-Fard Payar Radfar Majid E. Warkiani Ken O'Byrne Arutha Kulasinghe 《Immunology》2023,168(2):256-272
Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy. 相似文献
7.
As the most abundant natural biopolymer on earth, celluloses have long-term emerged as a capable platform for diverse purposes. In the context of metal nanoparticles applied to catalysis, the alternatives to traditional catalyst supports by using biomass-derived renewable materials, likely nanocelluloses, have been paid a great effort, in spite of being less exploited. In this study, cellulose nanocrystals were isolated from corn leaf via chemical treatment involving alkalizing, bleaching and acid hydrolysis. The crystallinity of obtained cellulose was evaluated in each step, focusing on the effects of reactant concentration and reaction time. Cellulose nanocrystals were characterized by powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), evidencing the presence of cellulose nanospheres (crystallinity index of 67.3% in comparison with 38.4% from untreated raw material) in the size range of 50 nm. Without using any additional surfactants or stabilizers, silver nanoparticles (AgNPs) well-dispersed on the surface of cellulose nanocrystals (silver content of 5.1 wt%) could be obtained by a simple chemical reduction using NaBH4 at room temperature. The catalytic activity was evaluated in the selective reductions of 4-nitrophenol towards 4-aminophenol and methyl orange towards aromatic amine derivatives in water at room temperature. The effects of catalyst amount and reaction time were also studied in both reduction processes, showing near-quantitative conversions within 5 minutes and obeying the pseudo-first-order kinetics, with the apparent kinetic rate constants of 8.9 × 10−3 s−1 (4-nitrophenol) and 13.6 × 10−3 s−1 (methyl orange). The chemical structure of the catalytic system was found to be highly stable during reaction and no metal leaching was detected in reaction medium, evidencing adaptability of cellulose nanocrystals in immobilizing noble metal nanoparticles.As the most abundant natural biopolymer on earth, celluloses have long-term emerged as a capable platform for diverse purposes. 相似文献
8.
Review on the Oncology Practice in the Midst of COVID-19 Crisis: The Challenges and Solutions 下载免费PDF全文
Pedram FadaviMohammad HoushyariAmir Shahram Yousefi Kashi Alireza Mosavi JarrahiFarnaz Roshanmehr Mohammad Ali BroomandSaleh SandoughdaranFarzad Taghizadeh-Hesary 《Asian Pacific journal of cancer prevention》2021,22(1):19-24
As of late 2019, the outbreak of novel coronavirus disease (COVID-19) –that started in China– has rapidly afflicted all over the world. The COVID-19 pandemic has challenged health-care facilities to provide optimal care. In this context, cancer care requires special attention because of its peculiar status by including patients who are commonly immunocompromised and treatments that are often highly toxic. In this review article, we have classified the main impacts of the COVID-19 pandemic on oncology practices –followed by their solutions– into ten categories, including impacts on (1) health care providers, (2) medical equipment, (3) access to medications, (4) treatment approaches, (5) patients’ referral, (6) patients’ accommodation, (7) patients’ psychological health, (8) cancer research, (9) tumor board meetings, and (10) economic income of cancer centers. The effective identification and management of all these challenges will improve the standards of cancer care over the viral pandemic and can be a practical paradigm for possible future crises. 相似文献
9.
Fatemeh Eghbalian Lotfollah Karimi Roya Raeisi Ayda Hasanpour Dehkordi Hamid Bouraghi 《Osong Public Health and Research Perspectives》2022,13(3):174
In neonates, bilirubin tends to be deposited in body tissues, especially the skin and mucous membranes. Jaundice is an early symptom of bilirubin excretion disorders. Therefore, the aim of this study was to investigate the effect of clofibrate on reducing neonatal jaundice. In this systematic review, international databases, including PubMed, Scopus, Web of Science, Embase, Cochrane, and Google Scholar, were searched without time and language restrictions. The reference lists of all studies ultimately included were manually searched. In the 17 articles reviewed, with a sample size of 665 people published between 2005 and 2019, the average weight of the neonates varied from 2,186 g to 4,000 g. Furthermore, the average age of neonates varied from 2 days to 9 days. Four doses of clofibrate (25, 30, 50, 100 mg/kg of neonatal body weight) were used. The bilirubin level of neonates significantly decreased in the intervention group 24, 36, 48, and 72 hours after the start of treatment. Clofibrate administration decreased total serum bilirubin, especially from the second day onwards, and also reduced hospitalization time, hospital costs, and side effects from hospitalization. 相似文献
10.