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R Rossi

Publications and source records attributed to R Rossi.

At least 73 records · Page 4Linked to original sources
PubMed2001

Differing ADP release rates from myosin heavy chain isoforms define the shortening velocity of skeletal muscle fibers.

To understand mammalian skeletal myosin isoform diversity, pure myosin isoforms of the four major skeletal muscle myosin types (myosin heavy chains I, IIA, IIX, and IIB) were extracted from single rat muscle fibers. The extracted myosin (1-2 microg/15-mm length) was sufficient to define the actomyosin dissociation reaction in flash photolysis using caged-ATP (Weiss, S., Chizhov, I., and Geeves, M. A. (2000) J. Muscle Res. Cell Motil. 21, 423-432). The ADP inhibition of the dissociation reaction was also studied to give the ADP affinity for actomyosin (K(AD)). The apparent second order rate constant of actomyosin dissociation gets faster (K(1)k(+2) = 0.17 -0.26 microm(-1) x s(-1)), whereas the affinity for ADP is weakened (250-930 microm) in the isoform order I, IIA, IIX, IIB. Both sets of values correlate well with the measured maximum shortening velocity (V(0)) of the parent fibers. If the value of K(AD) is controlled largely by the rate constant of ADP release (k(-AD)), then the estimated value of k(-AD) is sufficiently low to limit V(0). In contrast, [ATP]K(1)k(+2) at a physiological concentration of 5 mm ATP would be 2.5-6 times faster than k(-AD).

Adenosine Diphosphate↗
PubMed2001

Responses of thiols to an oxidant challenge: differences between blood and tissues in the rat.

Treatment of rats with diamide (100 mg/kg i.p.) altered the thiol components of the blood to a very different extent than in tissues (liver, kidney, lung, spleen, heart and testis). A total consumption (10 min) and regeneration (120 min) of blood glutathione (GSH), matched by a parallel increase and decrease in glutathione-protein mixed disulfides (GS-SP) was observed. In contrast, no modification of non-protein SH groups (NPSH) and protein SH groups (PSH), GS-SP and malondialdehyde (MDA) was observed in liver, kidney, lung, testis spleen and heart within same time range. In particular, only glutathione disulfide (GSSG) levels and some activities of antioxidant enzymes were modified to a small extent and in an opposite direction in some organs. For example, GSSG, and glucose-6-phosphate dehydrogenase (G-6-PDH) and catalase (CAT) activities appeared up-regulated in one tissue and down-regulated in another. The least modified organ was the liver, whereas lung and spleen were the most affected (lung, GSSG, significantly increased whereas G-6-PDH, glutaredoxin (GRX), GPX, superoxide dimutase (SOD) levels were significantly lowered; spleen, GSSG and the activity of glutathione reductase (GR), G-6-PDH and glutathione transferase (GST) were significantly decreased). The different responses of erythrocytes and organs to diamide were explained by the high affinity of hemoglobin and by the relatively high potential of thiol regeneration in organs. The rapid reversibility of the process of protein S-thiolation in blood and the small effects in organs leads us to propose the existence of an inter-organ cooperation in the rat that regulates protein S-thiolation in blood. Plasma thiols may well play a role in this process.

Animals↗
PubMed2001

Detection of hydroxyl radicals by D-phenylalanine hydroxylation: a specific assay for hydroxyl radical generation in biological systems.

Hydroxylation of l-phenylalanine (Phe) by hydroxyl radical (*OH) yields 4-, 3-, and 2-hydroxyl-Phe (para-, meta-, and ortho-tyrosine, respectively). Phe derivative measurements have been employed to detect *OH formation in cells and tissues, however, the specificity of this assay is limited since Phe derivatives also arise from intracellular Phe hydroxylase. d-Phe, the d-type enantiomer, is not hydroxylated by Phe hydroxylase. We evaluate whether d-Phe reacts with *OH as well as l-Phe, providing a more reliable probe for *OH generation in biological systems. With *OH generated by a Fenton reaction or xanthine oxidase, d- and l-Phe equally gave rise to p, m, o-tyr and this could be prevented by *OH scavengers. Resting human neutrophils (PMNs) markedly converted l-Phe to p-tyr, through non-oxidant-mediated reactions, whereas d-Phe was unaffected. In contrast, when PMNs were stimulated in the presence of redox cycling iron the *OH formed resulted in more significant rise of p-tyr from d-Phe (9.4-fold) than l-Phe (3.6-fold) due to the significant background formation of p-tyr from l-Phe. Together, these data indicated that d- and l-Phe were equally hydroxylated by *OH. Using d-Phe instead of l-Phe can eliminate the formation of Phe derivatives from Phe hydroxylase and achieve more specific, sensitive measurement of *OH in biological systems.

Cell Survival↗
PubMed2001

Pharmacological and toxicological aspects of 4-demethoxy-3'-deamino-3'-aziridinyl-4'-methylsulphonyl-daunorubicin (PNU-159548): a novel antineoplastic agent.

4-demethoxy-3'-deamino-3'-aziridinyl-4'-methylsulphonyl-daunorubicin (PNU-159548) belongs to a novel class of antitumor compounds (termed alkycyclines) and is currently undergoing Phase II clinical trial. In the present study, we investigated the in vitro and in vivo antitumor activity, the pharmacokinetics, and the toxicological profile of this compound. PNU-159548 showed good cytotoxic activity in murine and human cancer cells growing in vitro, with an average concentration for 50% growth inhibition of 15.8 ng/ml. The drug showed strong antitumor efficacy in vivo after i.v. and p.o. administration against rapidly proliferating murine leukemias and slowly growing transplantable human xenografts. At non-toxic doses, PNU-159548 produced complete regression and cures in ovarian, breast, and human small cell lung carcinomas. Fourteen of 16 models studied, including colon, pancreatic, gastric, and renal carcinomas, astrocytoma and melanoma, were found to be sensitive to PNU-159548. In addition, PNU-159548 was effective against intracranially implanted tumors. Toxicological studies revealed myelosuppression as the main toxicity in both mice and dogs. The maximum tolerated doses, after a single administration, were 2.5 mg/kg of body weight in mice, 1.6 mg/kg in rats, and 0.3 mg/kg in dogs. In the cyclic studies, the maximum tolerated doses were 0.18 mg/kg/day (cumulative dose/cycle: 0.54 mg/kg) in rats and 0.05 mg/kg/day (cumulative dose/cycle: 0.15 mg/kg) in dogs. PNU-159548 showed minimal cardiotoxicity, when compared with doxorubicin in the chronic rat model at a dose level inducing similar myelotoxicity. Animal pharmacokinetics, carried out in mice, rats, and dogs, was characterized by high volumes of distribution, plasma clearance of the same order of the hepatic blood flow, and short terminal half-life. These findings support the conclusion that PNU-159548 is an excellent candidate for clinical trials in the treatment of cancer.

Animals↗
PubMed2001

Altered glutathione anti-oxidant metabolism during tumor progression in human renal-cell carcinoma.

It has been proposed that oxidative stress develops in tumors, with important consequences for growth and progression. To investigate this hypothesis, we measured low m.w. thiols, disulfides, protein-mixed disulfides and a pool of major anti-oxidant enzymes in renal-cortex as well as renal-cell carcinoma (RCC) specimens at stages I-II and III. Our data showed (i) a significant increase in the levels of total intracellular glutathione at both tumor stages (levels were 2.6-2.8 fold higher than those in the normal renal cortex), (ii) a marked lowering of the GSH/GSSG ratio in stage I-II accompanied by a significant decrease of many GSH-dependent enzymes (i.e., GPX, GST, GGT, GR) and (iii) unchanged GSH/GSSG ratio and GSH-dependent enzyme activity in stage III with respect to normal renal cortex. These results indicate that relevant variations exist in the glutathione antioxidant system in the different stages of RCC and support the hypothesis that oxidative stress plays an important role in RCC growth and progression.

Adult↗
PubMed2001

Immunoreactivity for p27(KIP1) and cyclin E is an independent predictor of survival in primary gastric non-Hodgkin's lymphoma.

Our aim was to assess the prognostic implications of the expression of p27(KIP1) and cyclin E in gastric lymphoma. We investigated the prognostic value of the immunoreactivity of these molecules in 92 cases of primary gastric lymphoma: 34 LGMLs, 24 DLCLMLs and 34 DLCLs. p27 was positive in 88% of LGMLs, 71% of DLCLMLs and 32% of DLCLs (p = 0.004); cyclin E was positive in 9%, 33% and 59% of cases, respectively (p < 0.00001). p27/cyclin E immunoreactivity significantly correlated with histologic category, stage and LDH serum level. p27 immunoreactivity was significantly associated with better survival, whereas cyclin E reactivity was significantly related to worse outcome. Five-year CSS was 94% for patients with p27(+)/cyclin E(-) phenotype (n = 42), 79% for p27(+)/cyclin E(+) (n = 14) or p27(-)/cyclin E(-) (n = 16) phenotype and 60% for p27(-)/cyclin E(+) phenotype (n = 16) (p = 0.02). The prognostic role of p27/cyclin E expression was confirmed when analyzed separately within LGMLs and large-cell lymphomas. Immunoreactivity for p27 and cyclin E is an independent predictor of survival in PGLs that may be an adjunctive tool in identifying high-risk patients. It correlates with histologic category, stage and LDH serum level. p27(-)/cyclin E(+) phenotype is associated with worse survival, probably due to a synergistic effect of both cell-cycle defects. The predictive role of these molecules within each histologic group of PGLs deserves to be confirmed in larger series.

Adolescent↗
PubMed2001

Analysis of treatment failures and survival of patients with fallopian tube carcinoma: a cooperation task force (CTF) study.

OBJECTIVE: The objective of this retrospective multicenter study was to assess the pattern of failures and survival of patients with primary carcinoma of the fallopian tube. METHODS: The hospital records of 88 patients with primary carcinoma of the fallopian tube were reviewed. Surgery was the initial therapy for all patients. Tumor stage was I in 21 (23.9%), II in 21 (23.9%), III in 43 (48.8%), and IV in 3 (3.4%) patients. Postoperative treatment was given without well-defined protocols. The median follow-up of survivors was 55 months (range, 7-182). RESULTS: Of the 21 patients with stage I disease, 10 had no postoperative treatment and 11 had platinum-based chemotherapy. Five (23.8%) patients recurred after a median of 29 months (range, 8-93) from initial surgery. Of the 21 patients with stage II disease, 2 had no postoperative treatment, 2 underwent external pelvic irradiation, 16 received platinum-based chemotherapy, and 1 patient had oral melphalan. Eight (38.1%) patients recurred after a median of 25.5 months (range, 7-57). Of the 46 patients with stage III-IV disease, 1 patient refused chemotherapy and died after 19 months and 45 patients received platinum-based chemotherapy. A clinical complete response was obtained in 29 (64.4%) patients and a partial response in 8 (17.8%). A second-look laparotomy was performed in 14 of the 29 clinically complete responders: 12 patients were found to be in pathological complete response and 2 had persistent disease. Six (50.0%) of the former recurred after a median of 22 months (range, 13-101) from initial surgery. The two patients with persistent disease developed tumor progression after 15 and 11 months, respectively. Fifteen clinically complete responders did not undergo second-look, and 7 (46.7%) of them had a recurrence after a median of 18 months (range, 9-41). For the whole series, 5-year survival was 57%. By log-rank test, survival was related to FIGO stage (III-IV vs I-II, P = 0.0001), tumor grade (G3 vs G1 + G2, P = 0.0038), and patient age (>58.5 years vs <58.5 years, P = 0.0069), but not to histological type. The Cox model showed that FIGO stage (P = 0.0018) and patient age (P = 0.0290) were independent prognostic variables for survival. Among the patients with stage III-IV disease, 5-year survival was 55% for the patients who had residual tumor <1 cm compared with 21% for those who had larger residuum (P = 0.0169). CONCLUSIONS: Primary carcinoma of the fallopian tube shares several biological and clinical features with ovarian carcinoma. However, when compared with the latter, fallopian tube carcinoma more often tends to recur in retroperitoneal nodes and distant sites. Stage, patient age, and, among patients with advanced disease, residual tumor after initial surgery represent important prognostic variables for survival.

Adult↗
PubMed2001

Oxygen radical-mediated reduction in basal and agonist-evoked NO release in isolated rat heart.

Oxygen free radicals (OFR) play a primary role in ischemia-reperfusion-mediated vascular dysfunction and this is paralleled by a loss of endothelial nitric oxide synthase (eNOS) activity. The authors tested whether a direct exposure to OFR may affect vascular relaxation by altering nitric oxide (NO) release. Effects of electrolysis(EL)-generated OFR on basal and agonist-evoked NO release were monitored in isolated rat hearts by oxyhemoglobin assay. Electrolysis-induced changes were compared with those obtained after 30 min perfusion with NOS and cyclooxygenase (COX) inhibitors NG-nitro-L-arginine methyl ester (L-NAME, 100 microM) and indomethacin (INDO, 1 m M). Electrolysis-generated hydroxyl radical (.OH) formed by.O2-and H2O2 via the Fenton reaction as revealed by Electron Paramagnetic Resonance (EPR). After EL, basal NO release declined by 60% and coronary perfusion pressure (CPP) increased by approximately 70%. L-NAME/INDO perfusion similarly lowered NO release (-63%) but increased CPP less than EL (56+/-3%P<0.03 v post-EL). In presence of excess substrates and cofactors eNOS activity was not affected by EL. Both acetylcholine (ACh; 1 microM) and bradykinin (BK; 10 n M) had minimal effect in reversing EL-induced vasoconstriction, whereas both partially reversed L -NAME/INDO-mediated constriction. Sodium nitroprusside (SNP, 1 microM) completely reversed L-NAME/INDO constriction and partly countered that after EL (-38+/-2.5, P<0.001). Acetylcholine-evoked NO release was nearly abolished by both treatments whereas BK still elicited partial NO release after eNOS/cyclooxygenase inhibition (P<0.001) but not after EL. In conclusion, OFR severely impair NO-mediated coronary vasorelaxation affecting both basal and agonist-evoked NO release but not eNOS activity. However, EL also significantly blunts NOS/COX-independent vasodilation suggesting alteration of other vasodilatative pathways.

Acetylcholine↗
PubMed2001

Turner's syndrome mosaicism 45X/47XXX: an interesting natural history.

Mosaicism 45X/47XXX is a sporadic form of ovarian dysgenesis. Many of the cases previously described were characterized by a variable phenotype expression. We here report the case of a 33-yr-old woman with recent secondary amenorrhea, weight loss and breast regression. Her menarche had occurred at the age of 11 yr and 6 months and her menstrual cycles had been regular until the age of 28; then, oligomenorrhea and hypertricosis developed. A pelvic ultrasound showed enlarged polycystic-like ovaries and normal uterus. She was treated with ethynil-estradiol and cyproterone acetate for one year. At the age of 31 yr, she underwent a pelvic ultrasound--which revealed normal volume of the ovaries--and hormonal assays including FSH (69 UI/l), LH (113 UI/l), 17beta-estradiol (88 pg/ml), plasma androgens and cortisol levels within normal ranges. No organ-specific autoantibodies toward ovaries, steroid-producing cells or adrenals were found. At the age of 33 yr, there was ultrasound evidence of streak-like ovaries. The patient's height was 145 cm and her weight 45 kg. She had normal female external genitalia, abnormal upper-to-lower body segment ratio, webbed neck, low posterior hair line, cubitus valgus, short and asymmetrical 4th metacarpi, hallux with lateral deviation and moderate scoliosis. No increase in ovarian steroids were found after GnRH-analogue triptorelin (0,1 mg sc) administration. The karyotype analysis on peripheral blood lymphocytes showed a mosaic 45X (90% cells) and 47XXX (10% cells). Diagnostic pelviscopy confirmed streak gonads. Chronic lymphocytic thyroiditis was diagnosed but no cardiovascular or kidney abnormalities were found. A neuro-psychological evaluation revealed emotional and social immaturity, disorders in motorial coordination, visual-spatial organization, as well as reading difficulties and impaired complex phrase construction. The presence of several somatic features of Turner's syndrome, neuro-psychological disorders and an interesting natural history probably depended on the quantitative proportion of 45X to 47XXX cell-lines in different tissues and organs. Estrogen and progestin replacement therapy led to weight gain, re-appearance of secondary sexual characteristics and a mild improvement in mental equilibrium.

Adult↗
PubMed2001

Effects of microenvironment on morphology and function of the microglial cell line BV-2.

Effects of microenvironmental changes were examined in the microglial cell line BV-2. In serum supplemented medium cells were ameboid shaped and exhibited thin cytoplasmatic processes at lower concentration or in absence of serum. High levels of acetylated low-density lipoprotein (LDL) receptor and of phagocytic and proliferative activity were detected. Lipopolysaccharide (LPS) and the neuropeptide substance P (SP) induced secretion of interleukin-6. Low interleukin-3 secretion was detected only occasionally and was not influenced by LPS and SP. In defined medium, "process-bearing" cells were evident. Compared to cultures in serum supplemented medium, the cells expressed lower acetylated LDL-binding and phagocytic activity while actively proliferated, the response to LPS was reduced and to SP absent. Granulocyte/macrophage colony-stimulating factor increased the number of process-bearing cells, of acetylated LDL-binding and of IL-6 secretion induced by LPS. Cell morphology was not influenced by neurotrophins like nerve growth factor and brain-derived neurotrophic factor. The described phenotypical and functional plasticity makes the BV-2 cell line a useful model to investigate mechanisms of microglial activation.

Animals↗
PubMed2001

Chromosomal location and evolution of a satellite DNA family in seven sturgeon species.

The Hind III satellite DNA family, isolated from the Acipenser naccarii genome, was used as a probe for fluorescent in-situ hybridization (FISH) on the karyotype of seven sturgeon species, six belonging to the genus Acipenser and one to Huso. All species except one (A. sturio) exhibit from 8 to 80 chromosome hybridization signals, mainly localized at the pericentromeric regions. Eight chromosomes with weak hybridization signals are present in H. huso and A. ruthenus, which are characterized by a karyotype with about 120 chromosomes. The species with 240-260 chromosomes, A. transmontanus, A. naccarii, A. gueldenstaedtii, and A. baerii, show from 50 to 80 signals, prevalently localized around centromeres. Moreover, A. transmontanus and A. gueldenstaedtii show from 4 to 8 chromosomes with a double signal. The phylogenetic and evolutionary relationships among sturgeon species are discussed on the basis of number and morphology of signal-bearing chromosomes and on the localization of signals.

Animals↗
PubMed2001

Mutations in the gene encoding immunoglobulin mu-binding protein 2 cause spinal muscular atrophy with respiratory distress type 1.

Classic spinal muscular atrophy (SMA) is caused by mutations in the telomeric copy of SMN1. Its product is involved in various cellular processes, including cytoplasmic assembly of spliceosomal small nuclear ribonucleoproteins, pre-mRNA processing and activation of transcription. Spinal muscular atrophy with respiratory distress (SMARD) is clinically and genetically distinct from SMA. Here we demonstrate that SMARD type 1 (SMARD1) results from mutations in the gene encoding immunoglobulin micro-binding protein 2 (IGHMBP2; on chromosome 11q13.2-q13.4). In six SMARD1 families, we detected three recessive missense mutations (exons 5, 11 and 12), two nonsense mutations (exons 2 and 5), one frameshift deletion (exon 5) and one splice donor-site mutation (intron 13). Mutations in mouse Ighmbp2 (ref. 14) have been shown to be responsible for spinal muscular atrophy in the neuromuscular degeneration (nmd) mouse, whose phenotype resembles the SMARD1 phenotype. Like the SMN1 product, IGHMBP2 colocalizes with the RNA-processing machinery in both the cytoplasm and the nucleus. Our results show that IGHMBP2 is the second gene found to be defective in spinal muscular atrophy, and indicate that IGHMBP2 and SMN share common functions important for motor neuron maintenance and integrity in mammals.

Amino Acid Sequence↗
PubMed2001

Identification of interspecific hybrids by amplified fragment length polymorphism: the case of sturgeon.

The identification of interspecific hybrids represents an important issue for conservation biology and trade controls. In Italy, the commercial demand for sturgeon is rapidly increasing and interspecific hybrids represent a relevant part of aquacultural production. In this study we tested the suitability of the amplified fragment length polymorphism (AFLP) technique for sturgeon hybrid detection. Multilocus AFLP profiles were analysed by cluster analysis and assignment tests based on observed and simulated samples. Our results show that this approach can easily identify sturgeon hybrids, encouraging its application not only in sturgeon but also in other systematic groups.

Animals↗
PubMed2001

End points in studies on the prevention of deep vein thrombosis.

Clinically overt events are of obvious relevance for the outcome of patients. There is unanimous consensus of clinicians that these events should be prevented in clinical practice. In clinical trials on the prevention of deep vein thrombosis, symptomatic objectively confirmed venous thromboembolism is the most important outcome to be measured. However, because of the difficulties related to the measurement of clinically overt events, venography is the most commonly used method for end-point measurement in clinical trials on the prevention of venous thromboembolism. The limitations of venography leave a great need for the development of accurate noninvasive methods to be used as alternatives to venography. The end point must be tailored to the phase of the clinical trial. In phase I/II clinical trials, that are designed to evaluate the effectiveness of thromboprophylactic agents, it still is necessary to use the most accurate method for the diagnosis of deep vein thrombosis and to perform bilateral venography. When a new pharmacologic agent is compared with the "gold standard" agent, the use of symptomatic end points should be preferable.

Clinical Trials as Topic↗
PubMed2001

Aldosterone inhibition limits collagen synthesis and progressive left ventricular enlargement after anterior myocardial infarction.

BACKGROUND: The reparative process after myocardial infarction is related to active collagen synthesis. Previous experimental studies demonstrated that cardiac fibrosis is mediated by angiotensin II and aldosterone; this mechanism is not clearly confirmed in patients who have had a myocardial infarction. The aim of this study was to evaluate whether the suppression of aldosterone may be helpful in reducing postinfarction collagen synthesis (and progressive left ventricular dilation) in patients treated with an angiotensin-converting enzyme inhibitor for a recent myocardial infarction. METHODS: We enrolled 46 patients (ages 60+/-11 years, 34 males) with a first episode of anterior transmural thrombolized myocardial infarction. At hospital discharge patients were randomized to receive potassium canrenoate, an oral aldosterone inhibitor, 50 mg once daily (group 1, n = 24) or placebo (group 2, n = 22). All enrolled patients were on angiotensin-converting enzyme inhibitor therapy. The serum concentration of the aminoterminal propeptide of type III procollagen was used to measure the collagen synthesis rate; dosage was obtained before enrollment, at hospital discharge, and after 3, 6, and 12 months of follow-up. RESULTS: After 3, 6, and 12 months of treatment, the aminoterminal propeptide of type III procollagen serum levels was significantly higher in the placebo group compared with the aldosterone inhibitor group; after 6 and 12 months we observed significantly smaller left ventricular volumes in the active treatment group. CONCLUSION: Potassium canrenoate, combined with an angiotensin-converting enzyme inhibitor, may reduce postinfarction collagen synthesis and progressive left ventricular dilation.

Canrenoic Acid↗
PubMed2001

Beta-N-acetylhexosaminidase activity and isoenzyme profile in the kidney and urine of trained rats.

Lysosomes play an important role in the immune system functioning and are involved in different aspects of inflammatory reaction, repair processes and tissue damage at various levels. Among various effects, it is known that physical exercise influences the release of different lysosomal components. The aim of this study was to evaluate enzyme activity and isoenzymatic profile of beta-N-acetylhexosaminidase both in kidney and urine of normal and trained rats. Enzyme activity was measured by fluorimetric assay while beta-N-acetylhexosaminidase isoenzymes were separated using DEAE-cellulose chromatography. Hexosaminidase specific activity was significantly increased in urine of trained rats whereas there was no increase in the kidneys of trained rats. Indeed, no significant differences were observed in the isoenzyme profile of kidney and urine extracts from normal and trained rats. Our findings suggest the exercise-induced release of lysosomal enzymes is a functional effect and not due to disruption of lysosomal membranes.

Animals↗
PubMed2001

Etoposide induces the dispersal of DNA ligase I from replication factories.

In eukaryotic cells DNA replication occurs in specific nuclear compartments, called replication factories, that undergo complex rearrangements during S-phase. The molecular mechanisms underlying the dynamics of replication factories are still poorly defined. Here we show that etoposide, an anticancer drug that induces double-strand breaks, triggers the redistribution of DNA ligase I and proliferating cell nuclear antigen from replicative patterns and the ensuing dephosphorylation of DNA ligase I. Moreover, etoposide triggers the formation of RPA foci, distinct from replication factories. The effect of etoposide on DNA ligase I localization is prevented by aphidicolin, an inhibitor of DNA replication, and by staurosporine, a protein kinase inhibitor and checkpoints' abrogator. We suggest that dispersal of DNA ligase I is triggered by an intra-S-phase checkpoint activated when replicative forks meet topoisomerase II-DNA--cleavable complexes. However, etoposide treatment of ataxia telangiectasia cells demonstrated that ataxia-telangiectasia-mutated activity is not required for the disassembly of replication factories and the formation of replication protein A foci.

Antineoplastic Agents, Phytogenic↗