Comparison of the effects of fasting morning, fasting evening and fed bedtime administration of tenatoprazole on intragastric pH in healthy volunteers: a randomized three-way crossover study.

BACKGROUND: The effectiveness of proton pump inhibitors is influenced by meals and administration time. AIM: To compare the effects on intragastric acidity of times of dosing of tenatoprazole, a novel imidazopyridine-based proton pump inhibitor with a prolonged plasma half-life. METHODS: This randomized three-period crossover study included 12 Helicobacter pylori-negative healthy subjects, who received tenatoprazole 40 mg either fasting at 7.00 AM, fasting at 7.00 PM or fed at 9.30 PM for 7 days, with a 2-week washout between periods. Twenty-four hour intragastric pH was monitored on day 7 of each period. RESULTS: On day 7, median 24-h pH was 4.7, 5.1 and 4.7 after breakfast, dinner and bedtime dosing, respectively (P = 0.11), whereas night-time pH was 4.2, 5.0 and 4.4 (P = 0.13). The mean 24-h percentage of time over pH 4 was 62, 72 and 64 after breakfast, dinner and bedtime dosing, respectively (N.S.), and 54, 68 and 56 during night-time (P = 0.06). Nocturnal acid breakthrough incidence decreased from 100% at baseline to 83%, 55% and 75% after 7.00 AM, 7.00 PM and 9.30 PM dosing, respectively (P = 0.18), and its mean duration dropped from 6.2 to 2.8, 1.0 and 2.2 h, respectively (P < 0.05). CONCLUSION: Seven-day administration of tenatoprazole provides a prolonged duration of acid suppression, especially during the night-time, with little effect of food or time of dosing.

A comparative study of the early effects of tenatoprazole 40 mg and esomeprazole 40 mg on intragastric pH in healthy volunteers.

BACKGROUND: Tenatoprazole is a novel proton pump inhibitor with a seven-hour plasma half-life. AIM: To compare the effects of tenatoprazole 40 mg and esomeprazole 40 mg on intragastric acidity during the first 48 h in healthy volunteers. METHODS: This randomized two-period crossover study included 24 Helicobacter Pylori-negative subjects; tenatoprazole 40 mg or esomeprazole 40 mg daily were given before breakfast for two consecutive days, with a 2-week wash-out between the administration periods. Intragastric pH was monitored for 48 h. RESULTS: Over 48 h, tenatoprazole 40 mg exerted a more potent acid inhibition than esomeprazole 40 mg (median pH: 4.3 vs. 3.9, P < 0.08; per cent of time above pH 4: 57% vs. 49%, P < 0.03; proportion of subjects with at least half of the time above pH 4: 71% vs. 46%). These differences resulted from better night-time acid control with tenatoprazole 40 mg than esomeprazole 40 mg (first night median pH: 4.2 vs. 2.9, P < 0.0001; second night: 4.5 vs. 3.2, P < 0.0001). The duration of nocturnal acid breakthroughs was significantly reduced during both nights. In contrast, no significant difference was detected during the daytime periods between both regimens. CONCLUSION: Over the first 48 h, tenatoprazole 40 mg achieves a better overall and night-time control of gastric pH than esomeprazole 40 mg. The translation of better early control of acidity into clinical benefits deserves further studies.

Tenatoprazole, a novel proton pump inhibitor with a prolonged plasma half-life: effects on intragastric pH and comparison with esomeprazole in healthy volunteers.

BACKGROUND: Proton pump inhibitors control gastric acidity better during the day than at night, when nocturnal acid breakthrough can occur. Tenatoprazole is a novel proton pump inhibitor with a seven-fold longer plasma half-life. Aim : To compare the effects of tenatoprazole 20 mg (T20), tenatoprazole 40 mg (T40) and esomeprazole 40 mg (E40) on intragastric acidity in healthy volunteers. METHODS: This randomized, three-period, cross-over study enrolled 18 Helicobacter pylori-negative volunteers, who received E40, T20 and T40 once daily for 7 days with a 14-day washout between periods. Twenty-four-hour gastric pH monitoring was performed on day 7. Serum gastrin was assessed on day 8. RESULTS: T40 induced a more potent acid inhibition than T20 (24-h median pH: 4.6 vs. 4.0, P < 0.01; daytime: 4.5 vs. 3.9, P < 0.01; night-time: 4.7 vs. 4.1, P < 0.05). T40 was more potent than E40 (24-h median pH: 4.6 vs. 4.2, P < 0.05; night-time: 4.7 vs. 3.6, P < 0.01); the pH > 4 holding time was higher during the night for T40 than for E40: 64.3% vs. 46.8%, P < 0.01; the nocturnal acid breakthrough duration was significantly shorter for T40 than for E40. No significant gastrin increase was observed and all drugs were well tolerated. CONCLUSION: T40 is significantly more potent than T20 and E40 during the night. The therapeutic relevance of this pharmacological advantage deserves further study.

Exonuclease I of Saccharomyces cerevisiae functions in mitotic recombination in vivo and in vitro.

We previously described a 5'-3' exonuclease required for recombination in vitro between linear DNA molecules with overlapping homologous ends. This exonuclease, referred to as exonuclease I (Exo I), has been purified more than 300-fold from vegetatively grown cells and copurifies with a 42-kDa polypeptide. The activity is nonprocessive and acts preferentially on double-stranded DNA. The biochemical properties are quite similar to those of Schizosaccharomyces pombe Exo I. Extracts prepared from cells containing a mutation of the Saccharomyces cerevisiae EXO1 gene, a homolog of S. pombe exo1, had decreased in vitro recombination activity and when fractionated were found to lack the peak of activity corresponding to the 5'-3' exonuclease. The role of EXO1 on recombination in vivo was determined by measuring the rate of recombination in an exo1 strain containing a direct duplication of mutant ade2 genes and was reduced sixfold. These results indicate that EXO1 is required for recombination in vivo and in vitro in addition to its previously identified role in mismatch repair.

An upstream positive regulatory element in human GM-CSF promoter is recognized by NF-kappa B/Rel family members.

To further extend the previous analysis of cis-acting elements and cognate trans-acting factors that contribute to GM-CSF transcriptional regulations, we have examined a promoter region between -1742 and -2010. DNase I footprinting assays showed four protected sequences named A, B, C and D. DNA transfections in the T-lymphoid Mo cell line, which constitutively expresses GM-CSF, indicated that the A element, located between -2002 and -1984, has a positive role on transcription. Further characterization by electrophoretic mobility shift assays in the presence of different competitor oligonucleotides showed that this element binds a factor of the NF-kappa B/Rel family.

Characterization of a distal 5'-flanking region (-2010/-630) of human GM-CSF.

The 5'-flanking region of the human GM-CSF gene was subcloned from the phagic clone lambda J1-16 to detect cis-elements involved in GM-CSF constitutive expression. We determined and sequenced an uncharacterized promoter region of 1381 bp (-2010 to -630), named pPF2000. Putative binding sites of several transcriptional factors were found. Progressive deletion mutants of the PF2000 were analyzed by measuring the linked CAT activities, in constitutive (5637) and inducible (PEU) GM-CSF-producing cells. A positive distal sequence (268 bp), between -2010 and -1742, responsible for the high constitutive expression of GM-CSF in 5637 carcinoma cell line was found.

H and L ferritin gene expression in U937 cells induced to macrophage differentiation.

Ferritin is an ubiquitous protein that has been shown to regulate cell differentiation in several experimental systems. In this study we have investigated the expression of ferritin genes encoding the heavy (H) and light (L) chains in t'B U937 cell line, induced to differentiate to macrophage-like cells by 12-O-tetradecanoylphorbol-13-acetate (TPA), retinoic acid (RA) or 1-beta-D-arabinofuranosylcytosine (Ara-C). An increase in the level of H ferritin mRNA was detected in U937 cells that had been incubated with Ara-C. Treatment of U937 cells with Actinomycin D suggested that the H ferritin mRNA increase was mediated by post-transcriptional mechanisms. The L ferritin mRNA level increased only following stimulation of U937 cells with RA. Immunophenotypic and cytochemical analyses showed that Ara-C was the strongest inducer of the macrophagic differentiation of U937 cells. These results suggest that the increase of H ferritin mRNA expression may represent a sensitive marker of myeloid cells differentiating along the monocyte-macrophage lineage.

Spacer promoters are orientation-dependent activators of pre-rRNA transcription in Drosophila melanogaster.

In Drosophila melanogaster, 240-base-pair (bp) repeats, clustered in tandem arrays within the ribosomal DNA nontranscribed spacer region, include sites of RNA polymerase I-dependent transcription initiation and elements that stimulate the rate of transcription from the downstream precursor rRNA (pre-rRNA) promoter. We have analyzed the in vivo transcriptional activity of a large set of recombinant constructs in which tandem arrays of distinct segments derived from a 240-bp repeat were inserted upstream of the pre-rRNA promoter. The results indicate that activating spacer elements are confined to a region of 70 bp. Enhancing units overlap with spacer promoters, since DNA segments that stimulate transcription at the gene promoter also efficiently drive transcription initiation. The finding that artificial spacer arrays invariably stimulate pre-rRNA transcription initiation in an orientation-dependent fashion suggest that spacer-initiated transcription is involved in the enhancement process. The minimal spacer activating segment includes a perfect copy of a core domain of the gene promoter extending from -24 to +10 flanked by poorly homologous upstream DNA sequences. Spacer and gene promoters are functionally interchangeable as activating units. However, the different combination of DNA elements within the two determines a functional hierarchy, as only the pre-rRNA promoter is responsive to the stimulatory action of upstream units.

Synthesis of a 60 kD nuclear DNA binding protein induced by cytosine arabinoside in the HL 60 leukemic cell line.

Cytosine arabinoside (ara-C) is being employed at low dosage as differentiative rather than a cytotoxic agent in the therapy of leukemias. We have analyzed nuclear proteins from HL 60 leukemic cells treated with ara-C and have observed increased expression of a 60 kD protein in a dose-dependent fashion. This protein is actively synthesized, as assessed by labeled methionine incorporation. Using DNA cellulose affinity chromatography we could also demonstrate DNA binding properties of the 60 kD protein.

Isolation and characterization of a K562 cell line resistant to 1-beta-D-arabinofuranosylcytosine-mediated erythroid induction.

The isolation of a K562 cell line, K562(S)R, resistant to 1-beta-D-arabinofuranosylcytosine (ara-C)-mediated erythroid induction, is described. Ara-C (10-50 microM) inhibits cell growth of K562(S)R cells but is not able to activate the program of erythroid induction. This failure is associated with the lack in the increase of accumulation of epsilon-globin and gamma-globin mRNA sequences in ara-C-treated K562(S)R cells. This cell line could be of interest for studies focused on molecular mechanisms of activation of globin genes in K562 cells.

Effect of endothelial cell conditioned medium on the growth of human bone marrow fibroblasts.

Both endothelial cells (EC) and fibroblasts, two discrete populations of hemopoietic stroma, are known to modulate the proliferation and differentiation of hemopoietic progenitors. Recent reports also demonstrated that EC stimulate the in vitro growth of fibroblasts via a soluble factor. This finding seems to support the hypothesis that EC may play a role in the pathogenesis of bone marrow fibrosis in myeloproliferative disorders (MD). We have studied the effects of the conditioned medium (CM) from human umbilical vein EC cultures, obtained in serum free conditions, on the growth of bone marrow fibroblasts from normal donors and from patients with MD. The results show that EC derived CM contains a factor which stimulates the proliferation of fibroblasts and that can act as an authentic growth factor by inducing "quiescent" fibroblasts to proliferate. Moreover, we found that this endothelial derived growth factor (EDGF) equally promotes the proliferation of both normal and pathological progenitors of bone marrow fibroblasts (CFU-F) by increasing both the number and the size of the colonies.

[Attitude and social reaction of a sample of young people with regard to some types of criminal behavior]. / Atteggiamento e reazione sociale di un campione di giovani nei confronti di alcuni comportamenti criminosi.

The object of the present study is the analysis of how certain types of delinquent behaviour are noted by a group of young people, aged between 14 and 18 years, resident in the Milan area. Under the methodological profile a questionaire was made up including various hypotheses of behaviour of a criminal nature which those interviewed were asked to comment on not only on the level of mere approval/disapproval but also on the level of the attitude they considered it would be best to assume towards the hypothetical author of the crime. A clear homogeneity in the answers was found only on the level of the reaction of approval/disapproval, since all the sample of young people, with slight variations, was found to give a strongly disapproving judgement. With regard to the request for interventions on the operative level on the other hand a sort of dispersion was noted at the level of all the various possible answers contemplated. In such a perspective it is important to note how the request for penal interventions and, above all, specifically punitive interventions was particularly rarely encountered, and how the young people tended to favour an attempt to solve the problem in a more strictly private and psychological manner, involving the primary groups of ownership, through the indication of types of intervention to clarify and support the culprits, generally of a psychological nature, but in any case certainly not punitive.