PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “ceRNA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

180 records · Page 10Linked to original sources
PubMed1983

Use of uridine rescue to enhance the antitumor selectivity of 5-fluorouracil.

We examined the ability of uridine to increase the therapeutic index of 5-fluorouracil (FUra) against C57BL/6 X DBA/2 F1 mice bearing a Day 1 B16 melanoma or L1210 leukemia. FUra (400, 600, or 800 mg/kg, i.p.) followed in 24 hr by a 5-day s.c. infusion with uridine (5 g/kg/day, s.c.) was compared with the maximum tolerated dose of FUra (200 mg/kg, i.p.) plus a 5-day infusion with 0.9% NaCl solution. High-dose FUra plus delayed infusion with uridine was more effective than FUra (200 mg/kg) in inhibiting the growth of the B16 melanoma. High-dose FUra plus uridine rescue was, however, no more effective than FUra (200 mg/kg) in increasing the survival times of mice bearing the L1210 leukemia. To see if uridine rescue from FUra toxicity correlated with effects against a sensitive normal tissue, bone marrow nucleated cellularity of normal, non-tumor-bearing mice was monitored after drug treatment. In mice treated with FUra (200 mg/kg) followed in 24 hr by a 5-day infusion with either uridine (5 g/kg/day) or 0.9% NaCl solution, there was not as great a decrease in cellularity at the nadir with uridine, and, in addition, uridine accelerated recovery as compared to 0.9% NaCl solution. Furthermore, uridine (5 g/kg/day), but not thymidine (dThd) (5 g/kg/day) or 2'-deoxyuridine (dUrd) (5 g/kg/day), had a sparing effect on the depression in bone marrow nucleated cellularity seen at the nadir on Day 4 after Fura (200 mg/kg). The specificity of uridine to rescue mice from the lethal toxicity of the related fluorinated pyrimidines, 5-fluorouridine and 5-fluoro-2'-deoxyuridine, was also examined. Mice were treated with 5-fluorouridine (250 mg/kg, i.p.) followed in 24 hr by a 5-day infusion with uridine (1, 5, or 10 g/kg/day), dThd (1, 5, or 10 g/kg/day), or dUrd (1 or 5 g/kg/day). Uridine (1, 5, or 10 g/kg/day) rescued mice from the lethal toxicity of 5-fluorouridine, whereas dThd or dUrd was ineffective. Similarly, a 5-day infusion with uridine, but not dThd or dUrd, rescued mice from the lethal toxicity of 5-fluoro-2'-deoxyuridine (1800 mg/kg, i.p.).

Animals↗
PubMed1978

Effects of 5-fluorouracil on human colon carcinoma and solid rat Walker 256 carcinosarcoma: evaluation as in vitro predictors of clinical response.

Several biochemical effects of 5-fluorouracil (5-FU) including inhibition of the incorporation of 3H-deoxyuridine (3H-UdR) into DNA, inhibition of ribosome formation, and formation of 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP) were examined in samples of human colon carcinomas to determine if any of these drug effects might have predictive value as a reliable guide to 5-FU therapy. For comparison, the solid rat Walker 256 carcinosarcoma, which is only minimally responsive to 5-FU, was also studied. For each of the biochemical effects of 5-FU measured in the various samples of Walker 256 tumors, the responses were consistent and varied within a narrow range. In contrast, the formation of FdUMP from 5-FU and the degree of inhibition of the incorporation of 3H-UdR into DNA by 5-FU were extremely variable in the population of human colon carcinomas examined. In all human tumors examined, 5-FU caused a reduction in the formation of ribosomes, but even in the absence of 5-FU, the total amount of ribosome synthesis was so low that it makes measurement difficult to quantitate. Based on our data, a study might be warranted to determine if there is a correlation between FdUMP formation and responsiveness of colon carcinoma to 5-FU therapy.

Animals↗
PubMedDate not supplied

Biochemical and pharmacologic study of therapeutic synergism with cyclophosphamide plus methotrexate in murine L1210 leukemia.

The combination of cyclosphosphamide (CP) plus methotrexate (MTX) was found to be therapeutically synergistic against the L1210 ascites tumor. After inoculation with 1 x 10(6) L1210 cells to (C57BL/6 x DBA/2)F1 mice, ip administration of CP (200 mg/kg on Day 5) plus MTX (15 mg/kg on Days 5, 7, 9, and 11) resulted in a significant increase in mean lifespan, compared to optimal treatment with either CP or MTX alone. The contribution of the single, simultaneous dose of CP plus MTX on Day 5 to therapeutic synergism was examined. The combination of CP plus MTX on Day 5 produced a greater decrease in tumor cell numbers than either drug alone. Measurements of the time course of inhibition and recovery of 3H-deoxyuridine incorporation into DNA showed that within 48 hours, recovery of DNA synthesis in small intestine and bone marrow was almost complete after either CP, MTX, or CP plus MTX. In contrast, tumor, which had recovered within 48 hours after MTX, still remained greater than 90% inhibited after eight CP or CP plus MTX. Measurements of bone marrow nucleated cellularity after therapy showed that the single, simultaneous dose of CP plus MTX was no more toxic to bone marrow than CP alone, although it was more toxic than MTX alone. No alterations in the distribution of either MTX or alkylating metabolites of CP could be detected in tumor or normal tissues when CP and MTX were administered simultaneously.

Animals↗
PubMed1994

Class II alleles in juvenile arthritis in Czech children.

OBJECTIVE: Patients with pauciarticular and polyarticular onset rheumatoid factor (RF) negative juvenile arthritis (JA) have been reported to have a variety of HLA associations. The reason for the differences found in several recent studies is not known. We compare a new series of patients investigated in Prague, Czechoslovakia with those we reported from Dallas. METHODS: Czech patients with JA (N = 153) were classified clinically using the same criteria as in our studies in Dallas. The RF negative group included 56 patients that had persistent pauciarticular disease, 42 pauciarticular with polyarticular course and 39 with polyarticular onset. RF was present in 13 additional patients. HLA class II alleles were determined by oligotyping as previously described from our laboratory. RESULTS: DRB1*0801 was increased and DRB1*0701 was decreased in all the RF negative groups. The persistent pauciarticular group was associated with DRB1*11 and DPB1*0201 and lacked the association with DRB1*1301 seen in Dallas. Also found in Prague and not in Dallas were an increase in the frequency of DR2 in pauciarticular patients with early conversion and of DRB1*1201 in patients with iritis. Certain HLA associations (DRB1*0801, DPB1*0201) appear to be present in patients with JA in most studies; others (DRB1*1301, DPB1*0301) are more variable. CONCLUSION: The reason for differences in the HLA risk factors observed in our 2 populations is not known. Clinical heterogeneity not detected by our method seems the most likely explanation. Genetic and environmental factors may also play a role.

Alleles↗
PubMed1993

HLA class II alleles in juvenile dermatomyositis.

HLA class II alleles were investigated in 27 Czech patients (11 females and 16 males) with juvenile dermatomyositis. The immunogenetic investigation comprised determination of DRB1, DRB3, DRB5, DQA1, DQB1, and DPB1 alleles. Their prevalence was compared with that found in healthy Czech controls. No allele was found significantly more frequently in patients than in controls.

Adolescent↗
PubMed1993

Sequences of HLA alleles associated with arthritis in adults and children.

Adult rheumatoid factor (RF) positive rheumatoid arthritis (RA) and RF positive arthritis of childhood are associated with DRB1*0401 in Caucasians, and DRB1*0405 in Orientals, and in Ashkenazi and nonAshkenazi Jews. Certain other DRB1 alleles (DRB1*0101,1001) which have a similar sequence in the 3rd hypervariable region of the 1st domain are also associated with RA, but they appear to function as weaker risk factors. The difference in the relative strength of the associations is likely to be due to structural differences in the 1st and 2nd variable regions of the first domain of these alleles. Similarities and differences in the HLA associations between North American Caucasoid patients with juvenile arthritis in Dallas, TX, USA, and in Prague, Czechoslovakia, are discussed.

Adult↗
PubMed1995

Monitoring of human exposure to occupational genotoxicants.

The human exposure to genotoxic agents can be detected by using genetic monitoring procedures which is mainly concerned with markers of exposure and effect. Cytogenetic analysis of human peripheral lymphocytes and urine mutagenicity are routinely used in Hygiene Service of the Czech Republic. The review demonstrated the activity of National Reference laboratory and other laboratories in Hygiene Service of the Czech Republic in the problem dealing with monitoring of population exposure to genotoxic substances. Altogether, 7 regional and 15 district laboratories have been in function. Several thousands of occupationally exposed and control persons have been examined by now. The most followed population at risk were those exposed to cytostatics, polycyclic aromatic hydrocarbons, complex mixtures of chemicals, metals and others. The system of genetic monitoring helped to detect the exposure of population at risk to genotoxic contaminants, to use the obtained data for quantification of exposure and for preventive measures application and to control the efficacy of applied regulatory action.

Adult↗