Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004135 (ATM)
 13,001 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of bromodeoxyuridine (BrdU)-substituted DNA template and thymidine (dT) pool on excess sister-chromatid exchanges (SCEs) was studied in Bloom syndrome (BS) cells and an ataxia telangiectasia (AT)-derived mutant cell line (AsHa). When BS endomitotic cells were labeled with low and high (or high and low) BrdU concentrations during S1 and S2, only the BrdU concentration during S1 phase affected the observed SCE. In BS cells about a 10-fold increase in SCEs occurs during or following replication on a BrdU-substituted template (high-high and high-low BrdU labeling) relative to the normal DNA template. SCEs decreased to about half in AsHa cells labeled with various BrdU doses (40, 60, 80 and 100 micrograms/ml) during only S1, compared with those labeled during S1 and S2. Co-cultivation of AsHa and BS cells resulted in a significant reduction in SCE level from 70 to 13-17 in BS cells, lowered the BrdU concentrations necessary for sister-chromatid differential (SCD) staining from 40 to 10 micrograms/ml with normal SCE level and resulted in decreased level of SCEs at high BrdU concentrations (80-100 micrograms/ml) (12-14 SCE) in AsHa cells, compared with the originally increased SCE level (36.65 SCE at 100 micrograms/ml) without co-culture. However, co-cultivation between AsHa and normal cells lowered the BrdU dose necessary for SCD staining from 40 to 30 micrograms/ml; the dT pool possibly balanced at this level, which is clearly higher than that at co-cultivation between AsHa and BS cells. The reason for the very high BrdU doses needed to achieve SCD would seem to be that AsHa cells have high levels of thymidylate (TMP) synthetase, which maintain a large endogenous thymidine pool. This has been confirmed by direct measurement. These findings strongly support that excess and decreased dT pools are closely related to the condition necessary for high SCE induction.
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PMID:Bromodeoxyuridine (BrdU) template and thymidine pool effects on high frequencies of sister-chromatid exchange (SCE) in Bloom syndrome cells and a mutant cell line (AsHa) originated from ataxia telangiectasia. 237 55

The extracellular nucleotides, ATP and ADP, as well as adenosine have been implicated in a great number of physiological functions. ADP is one of the major platelet recruiting factors, whereas ATP is considered to be a competitive inhibitor of ADP-induced platelet aggregation and adenosine is able to induce vasodilatation and to inhibit platelet aggregation. The di- and triphosphate nucleosides can be hydrolyzed by members of several families of ectonucleotidases, including ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) and ecto-nucleotide pyrophosphatase/phosphodiesterases (E-NPPs) that, together with an ecto-5'-nucleotidase, catalyze adenosine formation. The renin-angiotensin system is the most important regulator of renal and cardiovascular functions and angiotensin II induces, physiologically, platelet activation. The aim of this study was to clarify the effects of ANGII and genetic hypertension upon extracellular nucleotide hydrolysis by rat platelet ectoenzymes. ANGII, in all tested doses (5, 50, 500 and 5000 pmol), was able to increase ATP (21, 31, 44 and 27%, respectively), ADP (22, 28, 78 and 37%, respectively) and AMP (40, 64, 60 and 64%, respectively) hydrolysis by rat platelets. Furthermore, losartan, a specific antagonist of the AT1 angiotensin-receptor, prevented the nucleotide hydrolysis effects. Additionally, an increase in AMP (about 144%) hydrolysis and a decrease in p-Nph-5'TMP (about 27%) hydrolysis were observed in platelets from spontaneously hypertensive rats (SHR) when compared to Wistar normotensive rats. We, herein, present data to demonstrate interactions between rat platelet angiotensinergic and adenosinergic systems that could contribute to the understanding and treatment of cardiovascular diseases such as hypertension, thrombosis and arteriosclerosis.
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PMID:The effects of angiotensin II and genetic hypertension upon extracellular nucleotide hydrolysis by rat platelet ectoenzymes. 1734

Antibiotics have raised significant concern as emerging pollutants for their increasing consumption, persistent input, and potential threat to ecological environment. Due to low concentrations and various types in coastal water, simultaneous quantification of all kinds of antibiotics is time-consuming and costly. In order to make antibiotic regular monitoring in coastal water possible, identifying the priority antibiotics in the environment is essential. Here, a method for screening the priority antibiotics in coastal water was proposed, considering individual antibiotic concentration, the positive correlation between individual and total antibiotic concentration, the detection frequency, and obvious ecological risk. Taking coastal water of the East China Sea as an example, on a list of 77 target antibiotics, 7 (SMX, TMP, SCP, SMP, CNX, ATM, and ETM) and 4 (SMX, SCP, SMP, and CNX) antibiotics were selected to be the priority antibiotics in 2017 and 2018, respectively. Furthermore, the 4 priority antibiotics in 2018 were all involved in the 7 priority antibiotics in 2017. The sum of the priority antibiotic concentrations accounted for 0.8% and 23.2% of total antibiotic concentrations, and the sum of their RQ accounted for 69.2% and 66.8% of total RQ values in 2017 and 2018, respectively. Among the above 7 priority antibiotics, ATM is mainly used in human clinical, SMX, SCP, and SMP are mainly consumed in veterinary medicine, TMP, CNX, and ETM are commonly used for humans and animals. The proposed method might provide an important reference for the monitoring and management of antibiotic pollution in coastal water.
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PMID:Identification of the priority antibiotics based on their detection frequency, concentration, and ecological risk in urbanized coastal water. 3277 9