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1.
C L Hew 《Canadian journal of biochemistry》1978,56(8):791-793
Poly(A)-containing ribonucleic acid from cod islet greatly stimulated the incorporation of radioactive amino acids into proteins when assayed in a wheat germ translation system. The translation products were examined by specific immunoprecipitation with guinea pig anti cod insulin antibodies and by extraction with acid--ethanol. These measurements revealed at least a fivefold increase in incorporation of labelled amino acid over the nonprogrammed system. Sodium dodecyl sulfate disc gel electrophoresis and gel filtration chromatography showed a product of molecular weight 12 500, a size considerably larger than cod proinsulin (9000). It is concluded that cod proinsulin is synthesized via a larger precursor, preproinsulin. 相似文献
2.
CM Vicient A Suoniemi K Anamthawat-Jnsson J Tanskanen A Beharav E Nevo AH Schulman 《The Plant cell》1999,11(9):1769-1784
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Gynura procumbens (Lour.) Merr. belongs to the Asteraceae Family. The plant is a well-known traditional herb in South East Asia and it is widely used to treat inflammation, kidney discomfort, high cholesterol level, diabetic, cancer and high blood pressure. Our earlier study showed the presence of valuable plant defense proteins, such as peroxidase, thaumatin-like proteins and miraculin in the leaf of G. procumbens. However, the effects of these defense proteins on cancers have never been determined previously. In the present study, we investigated the bioactivity of gel filtration fractionated proteins of G. procumbens leaf extract. The active protein fraction, SN-F11/12, was found to inhibit the growth of a breast cancer cell line, MDA-MB-231, at an EC50 value of 3.8 µg/mL. The mRNA expressions of proliferation markers, Ki67 and PCNA, were reduced significantly in the MDA-MB-23 cells treated with SN-F11/12. The expression of invasion marker, CCL2, was also found reduced in the treated MDA-MB-231 cells. All these findings highlight the anti-cancer property of SN-F11/12, therefore, the proteins in this fraction can be a potential chemotherapeutic agent for breast cancer treatment. 相似文献
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Background
Designing maximally selective ligands that act on individual targets is the dominant paradigm in drug discovery. Poor selectivity can underlie toxicity and side effects in the clinic, and for this reason compound selectivity is increasingly monitored from very early on in the drug discovery process. To make sense of large amounts of profiling data, and to determine when a compound is sufficiently selective, there is a need for a proper quantitative measure of selectivity. 相似文献6.
7.
Rupert CM Jones Maria Dickson-Spillmann Martin JC Mather Dawn Marks Bryanie S Shackell 《Respiratory research》2008,9(1):62
Background
Guidelines on COPD diagnosis and management encourage primary care physicians to detect the disease at an early stage and to treat patients according to their condition and needs. Problems in guideline implementation include difficulties in diagnosis, using spirometry and the disputed role of reversibility testing. These lead to inaccurate diagnostic registers and inadequacy of administered treatments. This study represents an audit of COPD diagnosis and management in primary care practices in Devon.Methods
Six hundred and thirty two patients on COPD registers in primary care practices were seen by a visiting Respiratory Specialist Nurse. Diagnoses were made according to the NICE guidelines. Reversibility testing was carried out either routinely or based on clinical indication in two sub-samples. Dyspnoea was assessed. Data were entered into a novel IT-based software which computed guideline-based treatment recommendations. Current and recommended treatments were compared.Results
Five hundred and eighty patients had spirometry. Diagnoses of COPD were confirmed in 422 patients (73%). Thirty nine patients were identified as asthma only, 94 had normal spirometry, 23 were restrictive and 2 had a cardiac disorder. Reversibility testing changed diagnosis of 11% of patients with airflow obstruction, and severity grading in 18%. Three quarters of patients with COPD had been offered practical help with smoking cessation. Short and long-acting anticholinergics and long acting beta-2 agonists had been under-prescribed; in 15–18% of patients they were indicated but not received. Inhaled steroids had been over-prescribed (recommended in 17%; taken by 60%), whereas only 4% of patients with a chronic productive cough were receiving mucolytics. Pulmonary rehabilitation was not available in some areas and was under-used in other areas.Conclusion
Diagnostic registers of COPD in primary care contain mistakes leading to inaccurate prevalence estimates and inappropriate treatment decisions. Use of pre-bronchodilator readings for diagnosis overestimates the prevalence and severity in a significant minority, thus post bronchodilator readings should be used. Management of stable COPD does often not correspond to guidelines. The IT system used in this study has the potential to improve diagnosis and management of COPD in primary care. 相似文献8.
Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.9.
Wenhui Nie Beiyuan Fu Patricia CM O'Brien Jinhuan Wang Weiting Su Alongkoad Tanomtong Vitaly Volobouev Malcolm A Ferguson-Smith Fengtang Yang 《BMC biology》2008,6(1):18
Background
Flying lemurs or Colugos (order Dermoptera) represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires), the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. 相似文献10.
Several studies have indicated that olfactory responses are impeded byamiloride. Therefore, it was of interest to see whether, and if so which,olfactory epithelial cellular compartments have amiloride- sensitivestructures. Using ultrastructural methods that involved rapid freezing,freeze-substitution and low temperature embedding of olfactory epithelia,this study shows that, in the rat, this tissue is immunoreactive toantibodies against amiloride sensitive Na(+)- channels. However, microvilliof olfactory supporting cells, as opposed to receptor cilia, contained mostof the immunoreactive sites. Apices from which the microvilli sprout andreceptor cell dendritic knobs had much less if any of theamiloride-antibody binding sites. Using a direct ligand-bindingcytochemical method, this study also confirms earlier ones that showed thatolfactory receptor cell cilia have Na+, K(+)-ATPase. It is proposed thatsupporting cell microvilli and the receptor cilia themselves havemechanisms, different but likely complementary, that participate inregulating the salt concentration around the receptor cell cilia. In thisway, both structures help to provide the ambient mucous environment forreceptor cells to function properly. This regulation of the saltconcentration of an ambient fluid environment is a function that theolfactory epithelium shares with cells of transporting epithelia, such asthose of kidney. 相似文献