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N Santoro

Publications and source records attributed to N Santoro.

At least 37 records · Page 2Linked to original sources
PubMed2001

The Candida glabrata Amt1 copper-sensing transcription factor requires Swi/Snf and Gcn5 at a critical step in copper detoxification.

The yeast Candida glabrata rapidly autoactivates transcription of the AMT1 gene in response to potentially toxic copper levels through the copper-inducible binding of the Amt1 transcription factor to a metal response element (MRE) within a positioned nucleosome. Our previous studies have characterized the role of a 16 bp homopolymeric dA:dT DNA structural element in facilitating rapid Amt1 access to the AMT1 promoter nucleosomal MRE. In this study, we have used the genetically more facile yeast Saccharomyces cerevisiae to identify additional cellular factors that are important for promoting rapid autoactivation of the AMT1 gene in response to toxic copper levels. We demonstrate that the Swi/Snf nucleosome remodelling complex and the histone acetyltransferase Gcn5 are both essential for AMT1 gene autoregulation, and that the requirement for these chromatin remodelling factors is target gene specific. Chromatin accessibility measurements performed in vitro and in vivo indicate that part of the absolute requirement for these factors is derived from their involvement in facilitating nucleosomal access to the AMT1 promoter MRE. Additionally, these data implicate the involvement of Swi/Snf and Gcn5 at multiple levels of AMT1 gene autoregulation.

Acetylation↗
PubMed2001

Stages of Reproductive Aging Workshop (STRAW).

A select group of clinicians and investigators met recently for the express purpose of developing a staging system for female reproductive aging. The group also addressed the confusing and redundant nomenclature that is commonly used to describe the late reproductive years. A summary and recommendations are presented.

Aging↗
PubMed2001

Effects of aging and estradiol supplementation on GH axis dynamics in women.

GH and IGF-I secretion decrease with age. The decline in serum GH with age appears to be associated with menopause. Prior studies of GH release before and after oral and transdermal hormonal replacement in the postmenopausal patient have shown no change or an increase in GH secretion. To distinguish the somatotropic axis effects of aging from those of estrogen deficiency, we compared eight prematurely menopausal women, aged 25-40 yr, with eight postmenopausal women, aged 51-70 yr, both before and after estradiol replacement. All women had a body mass index below 28 kg/m2. All were evaluated twice with frequent blood sampling every 10 min for 24 h. Studies were performed in the absence of exogenous hormones and 6-8 wk after transdermal estradiol replacement, targeted to achieve a serum estradiol level of 367 pmol/liter. GH pulsatility was analyzed. Variables tested included mean GH levels, interpulse baseline mean, pulse frequency per 24 h, and pulse amplitude. Transdermal estrogen replacement had a significant effect on mean GH levels and mean basal GH levels in both the premature ovarian failure and the age-appropriate postmenopausal group. No differences were noted in GH pulse frequency, GH pulse amplitude, IGF-I, IGF-binding protein-1, and IGF-binding protein-3 before and after treatment. A pronounced age effect was noted between the two groups. The premature ovarian failure women secreted significantly greater mean GH than the age-appropriate postmenopausal group regardless of treatment, with a significance level of P = 0.026. Interpulse baseline GH means were greater in the premature ovarian failure women than in the age-appropriate postmenopausal group, but the significance of this relationship was obliterated after adjustment for body mass index. Pulse amplitude was significantly increased in the premature ovarian failure women compared with age-appropriate postmenopausal women (P = 0.006). No significant changes were detected in the GH pulse frequency between the premature ovarian failure and postmenopausal groups. We conclude that moderate doses of transdermal estradiol supplementation do not exert a great effect on the somatotropic axis in women. Age and body composition appear to be the predominant influences on GH activity in women.

Adult↗
PubMed2001

Mutational screening of the CART gene in obese children: identifying a mutation (Leu34Phe) associated with reduced resting energy expenditure and cosegregating with obesity phenotype in a large family.

Cocaine- and amphetamine-regulated transcript (CART) inhibits feeding and induces the expression of c-Fos in hypothalamic areas implicated in appetite regulation. Furthermore, the CART peptide is found in neurons regulating sympathetic outflow, which in turn play an integral role in regulating body temperature and energy expenditure. The CART gene was screened by single-strand conformation polymorphism and automatic sequencing in 130 (72 girls) unrelated obese Italian children and adolescents. Their Z-scores (mean +/- SD) of relative to BMI percentiles was 3.9 +/- 1.8, and the average age at obesity onset was 4.7 +/- 2.6 years. Two previously described silent polymorphisms were found in the 3' untranslated region: an adenine deletion at position 1457 in 9 patients (allele frequency 0.035) and an A/G substitution at position 1475 in 11 patients (allele frequency 0.042). We found no difference between the obese patients heterozygous for one of these polymorphisms and those patients homozygous for the wild allele with respect to their age of obesity onset, BMI Z-scores, and leptin levels. A missense mutation of G729C resulting in the substitution of Leu with Phe at codon 34, within the NH2-terminal CART region, has been detected in the heterozygous state in a 10-year-old obese boy who has been obese since the age of 2 years. The patient belongs to a large family of obese subjects. The mutation cosegregated with the severe obesity phenotype over three generations and was not found in the control population. Resting metabolic rates were lower than expected in the propositus (-14%) and his mother (-16%), who carried the mutation. Leucine at codon 34, conserved in this position in the human and in the rat sequences, immediately precedes a couple of lysine residues that may well represent a dibasic processing site. The Leu34Phe mutation might alter the susceptibility to proteolysis of this potential processing site, likely altering the CART effect on thermogenesis and energy expenditure.

Adolescent↗
PubMed2001

Treatment of childhood acute lymphoblastic leukemia. Long-term results of the AIEOP-ALL 87 study.

BACKGROUND AND OBJECTIVES: In March 1987 AIEOP started the AIEOP-ALL-87 study, based on the previous AIEOP-ALL-82. The aim of this new study was to evaluate, for all risk groups: a) the efficacy of treatment intensification achieved by adding a fourth drug (daunomycin) in the induction phase and a 3-drug reinduction phase for all risk groups; b) the impact of the addition of three doses of intrathecal methotrexate during cranial radiotherapy and extended exposure to weekly high-dose L-aspariginase during late intensification in high risk patients. We report the long-term results of the AIEOP ALL-87 study. DESIGN AND METHODS: From 1987 to 1991, a total of 632 eligible and evaluable children (age 1 to < or =16 years) with non-B-cell acute lymphoblastic leukemia (ALL), were enrolled and stratified as follows: standard risk (SR, 79 patients, 12.5%) had WBC <10,000/mm3, age > or = 3 and <7 years, and FAB L1 morphology. The high risk (HR, 175 patients, 27.7%) group included patients with WBC > or =50,000/mm3 or FAB L3 morphology or T immunophenotype or acute undifferentiated leukemia (AUL) or leukemia-lymphoma syndrome. All the remaining patients formed the intermediate risk group (IR, 378 patients, 59.8%). All patients received a 4-drug induction therapy; intermediate-dose methotrexate was given to HR patients; cranial radiotherapy was given to IR and HR patients, while SR patients received extended intrathecal methotrexate; all patients received a 3-drug reinduction phase; high dose L-asparaginase (HD-L-ASP; E.Coli, Bayer) was given to HR patients; continuation therapy with 6-mercaptopurine, i.m. methotrexate, and monthly vincristine and prednisone pulses was given to all patients. Treatment duration was 2 years. RESULTS: Six hundred and nineteen patients (97.9%) achieved complete remission. The remission rate was 98.7% in the SR group, 98.1% in the IR group, and 97.1% in the HR group. The overall 10-year survival and event-free survival (EFS) rates (SE) are 74.7% (1.8) and 62.8% (2.0) respectively; EFS rates by risk group are 67.5% (5.5) in SR, 62.8% (2.6) in IR, and 61.9% (3.8) for HR. The 10-year EFS for all eligible patients was 63.9% (1.9). INTERPRETATION AND CONCLUSIONS: When compared to the results of the AIEOP-ALL-82 study, treatment intensification in the ALL-87 study has improved long-term survival and EFS from 66.4% and 53.6% to 74.7% and 62.8%, respectively. Failures were mostly due to marrow or extramedullary relapses suggesting that further treatment intensification, as being used in current therapeutic strategies, is appropriate, although patients relapsing after less intensive treatment may have better chances of rescue. These results, although obtained in a relatively large proportion of patients, in which infants were not included, indicate that the addition of high-dose L-asparaginase to a relatively non-intensive treatment may be of major benefit for HR patients and that the addition of intrathecal methotrexate during CRT, may improve the central nervous system-disease control with a marked reduction of nervous system relapses.

Adolescent↗
PubMed2001

Executive summary: Stages of Reproductive Aging Workshop (STRAW).

A select group of investigators attended a structured workshop, the Stages of Reproductive Aging Workshop (STRAW), at Park City, Utah, USA, in July 2001, which addressed the need in women for a staging system as well as the confusing nomenclature for the reproductive years.

Aging↗
PubMed2000

Pleuropulmonary blastoma: management and prognosis of 11 cases.

BACKGROUND: Pleuropulmonary blastoma (PPB) is a rare and aggressive malignant tumor that affects children and adults. This neoplasm is histologically characterized by primitive blastema and a malignant mesenchymal stroma that often demonstrates multidirectional differentiation. Despite the introduction of multimodal therapy, the prognosis of patients with PPB remains poor. METHODS: In the current study the authors reported on PPB cases from a national retrospective search performed in 18 Italian Associations for Pediatric Hematology and Oncology centers. Clinical data, surgical notes, pathologic findings, and summaries of chemotherapy and radiotherapy were obtained from reports and correlated with outcome by standard statistical methods. RESULTS: The series included 11 patients (7 boys and 4 girls) with a median age of 32 months. Respiratory distress was the most common clinical symptom. In three patients the PPB developed from other primary dysplastic diseases: cystic adenomatoid malformation in one case and congenital lung cysts in the other two cases. Five patients experienced disease recurrences (local recurrence in three patients and distant metastasis in two patients, within the central nervous system and an intraocular location, respectively). Patients with a type 2 histologic pattern and/or pleural involvement were found to have a worse outcome compared with patients without such features. Event free survival at 2 years from the time of diagnosis was 45% for all patients. Overall survival at 2 years was 72% for all patients. CONCLUSIONS: PPB is an aggressive neoplasm of early childhood and to the authors' knowledge no adequate therapy has been defined to date for patients with PPB. After making the diagnosis, the main goal of therapy should be radical surgery, even in patients with microscopic residual disease. Because the response to chemotherapy is poor, the authors' experience suggests that chemotherapy should be given with local radiotherapy in the majority of patients.

Child↗
PubMed2000

Wernicke's encephalopathy induced by total parenteral nutrition in patient with acute leukaemia: unusual involvement of caudate nuclei and cerebral cortex on MRI.

We report a 13-year-old girl with leukaemia and Wernicke's encephalopathy induced by total parenteral nutrition. MRI showed unusual bilateral lesions of the caudate nuclei and cerebral cortex, as well as typical lesions surrounding the third ventricle and aqueduct. After intravenous thiamine, the patient improved, and the abnormalities on MRI disappeared.

Acute Disease↗
PubMed2000

Thrombin generation in children with acute lymphoblastic leukemia: effect of leukemia immunophenotypic subgroups.

Elevated plasma concentrations of endogenous thrombin generation markers and thrombotic events have been reported in children with leukemia. The aim of this study was to evaluate the effects of cancer and its treatment on thrombin generation (TAT levels) in children with acute lymphoblastic leukemia (ALL). The authors evaluated 32 children (23 M, 9 F) aged between 1 and 15 years (mean 6) affected by ALL (immunophenotypic subgroups: 16 common, 7 T, and 9 pre-B type). In all patients TAT levels at onset and after 5-6 doses of L-asparaginase were evaluated. TAT levels were higher in patients both at onset (13.04 +/- 10.90 ng/L) and after the 5-6 doses of L-asp (19.41 +/- 11.05 ng/L) with respect to controls (4 +/- 1 ng/L) (p < .001 and p < .001). TAT levels after 5-6 doses of L-asp were higher than those at onset (p < .001). Factorial ANOVA showed that at onset there was a significant effect of leukemia immunophenotypic subgroups upon TAT levels (p < .05) and no effect of inherited thrombotic risk factors. These results indicate that in children with ALL an important role is played by acquired thrombotic risk factors, among which the indirect cancer procoagulant activity has its importance.

Adolescent↗
PubMed2000

Luteal progesterone relates to histological endometrial maturation in fertile women.

To examine the relationship between endometrial histological maturation and reproductive hormones, we studied 11 fertile women, aged 18-37 yr. All participants had had at least 1 previous pregnancy and cycled regularly, every 25-35 days. Women collected daily, first morning voided urine for measurement of estradiol and progesterone metabolite excretion, estrone conjugates (E1c), and pregnanediol glucuronide (Pdg), respectively, throughout the cycle of study. Hormones were normalized for creatinine. Between 7-9 days after home detection of a LH surge (Sure Step), participants underwent an endometrial biopsy using a small bore (Pipelle) catheter. Tissue was prepared for histological and biochemical analyses. The histological analysis is reported herein. Endometrium was dated by 3 authors (N.S., D.H., and S.P.), all of whom were blinded to the participant's identity or timing of biopsy within her cycle. Final dating was agreed upon based upon the method of Noyes et al. E1c and Pdg were integrated throughout the cycle using the trapezoidal rule, and correlations were sought between deviation from expected histology (based upon urinary hormones and LH surge) and integrated hormone values. E1c varied over a 2-fold range in these normal women, from 1196-2040 ng/cycle. Pdg excretion was much more variable, ranging from 22-119 microg/cycle. No relationship could be found between histological lagging of endometrial maturation and lower excretion of E1c. A moderate correlation was observed (Spearman's r = 0.6; P < 0.05) between degree of histological maturation and integrated Pdg. Of two women with evidence of a disparity between gland and stromal development (glands lagging behind stroma by >2 days), one excreted 24 microg Pdg/cycle, the next to lowest value. We conclude that normal fertile women experience a wide range of hormone concentrations in the face of normal endometrial maturation. Progesterone appears to exert a dose-related effect on endometrial maturation, and the techniques we used, although relatively crude clinical measures, appeared to be sufficient to detect this relationship.

Adolescent↗
PubMed1999

Decreased inhibin tone and increased activin A secretion characterize reproductive aging in women.

OBJECTIVE: We hypothesized that the increased FSH noted in older reproductive-aged women is due to both decreased inhibin and increased activin A secretion. DESIGN: Comparative clinical study. SETTING: An academic research center. PATIENT(S): Five cycling women, aged 43 to 47, were compared to five midreproductive women, aged 19 to 38. INTERVENTION(S): Specimens taken every 2 to 3 days were assayed for inhibin A and B and activin A. MAIN OUTCOME MEASURE(S): Integrated concentrations of inhibin A, inhibin B, and activin A in the follicular phase, luteal phase, and whole cycle. RESULT(S): Follicular inhibin B was reduced in older versus younger women (504 +/-82 versus 748+/-72 total pg). Luteal inhibin A was reduced in older versus younger women (668 +/-72 versus 1152+/-216 total pg). Activin A was elevated throughout the cycle of older versus younger women, without within-cycle fluctuations (21+/-2 versus 11+/-1 total ng). CONCLUSION(S): Lack of restraint by inhibin A and inhibin B contributes to the FSH rise associated with reproductive aging. This loss of restraint occurs in a tandem fashion, with inhibin B reduction before ovulation and inhibin A reduction after ovulation. Activin A may also play an endocrine role in maintaining elevated FSH in older reproductive-aged women.

Activins↗
PubMed1999

Polycystic ovary syndrome and ovarian autoimmunity--assessment of ovarian antibodies by EIA.

There are conflicting reports of an association of ovarian antibodies, detected by immunofluorescence, with polycystic ovary syndrome (PCOS). The objective of this study was to evaluate the association of ovarian autoimmunity with PCOS. A validated immunoassay for ovarian antibodies was used to assess serum from women with PCOS and with menopause and normal cycling women as controls. The frequency of ovarian antibodies was similar (25%) among the controls and PCOS. Thus, unlike the association of ovarian antibodies detected with this test in patients with unexplained infertility and premature menopause, the prevalence of ovarian antibody in patients with PCOS is not significantly different to controls.

Aged↗
PubMed1999

Bloodstream infections in children with cancer: a multicentre surveillance study of the Italian Association of Paediatric Haematology and Oncology. Supportive Therapy Group-Infectious Diseases Section.

A one-year prospective, multicentre surveillance study on aetiology, main clinical features and outcome of bloodstream infections in children with cancer was conducted in 18 paediatric haematology centres belonging to the Italian Association for Paediatric Haematology and Oncology. A total of 191 bloodstream infections were reported during the study period. Of them, 123 (64%) occurred in neutropenic and 68 (36%) in non-neutropenic patients. Gram-positive cocci caused 45% (85/191) of the episodes, gram-negative rods 41% (78/191), and fungi 9% (18/191). The remaining 5% (10/191) of the episodes were poly-microbial infections. A total of 204 pathogens were isolated (46% gram-positive cocci; 44% gram-negative rods; and 10% fungi). The aetiologic distribution was similar among neutropenic and non-neutropenic patients. A correlation between the infection and the presence of an indwelling central venous catheter was found in 20% (23/114) of the episodes among neutropenic patients and in 55% (23/62) among non-neutropenic patients. Gram-negative micro-organisms were isolated in an unusually high proportion of catheter-related infections (48%). The overall mortality rate from any cause within 30 days from the first positive blood culture was 11%, and was higher among patients who were neutropenic at the onset of the infection than among those who were not neutropenic (15 versus 4%, P = 0.03). In addition, the mortality was significantly higher in recipients of bone marrow transplantation than in patients with acute leukaemia or solid tumour (21, 11 and 6%, respectively) and was also higher in fungaemias and poly-microbial infections (22 and 30%) than in single gram-positive and gram-negative bacteraemias (11 and 6%).

Bacteremia↗
PubMed1999

The breakpoints of a constitutional inversion of chromosome 9 associated with haemophagocytic lymphohistiocytosis are not linked to the disease gene.

Haemophagocytic lymphohistiocytosis (HLH) is a severe disorder of early infancy consistent with an autosomal recessive inheritance. Neither the genetic locus nor the biochemical defect is known for the disease. A constitutional pericentric inversion of chromosome 9, with breakpoints in bands 9p23 and 9q31, has been reported in a case of HLH, suggesting a possible relationship between this chromosome abnormality and the disease. We investigated such an association, performing a genetic linkage analysis in a set of five consanguineous HLH families. 27 polymorphic markers on chromosome 9 were studied, excluding most of chromosome 9 as a putative site for the HLH gene.

Chromosome Breakage↗
PubMed1999

Differences in urinary excretion patterns of the hLH beta core fragment in premenopausal, perimenopausal, and postmenopausal women.

OBJECTIVE: The heterodimeric luteinizing hormone beta core fragment (hLH beta cf) is a highly stable urinary analyte reflective of circulating hLH. It is measured easily because of its high molar content and has none of the multiple isoforms and subunit dissociation problems of LH urinary measurements. As part of a long-term effort to develop new biochemical assays to stage women during the perimenopausal transition, we have examined the patterns of urinary excretion of this metabolite of hLH in premenopausal, perimenopausal, and postmenopausal women. DESIGN: We measured the concentration of the hLH beta cf in 10 consecutive first morning void urine specimens from premenopausal, perimenopausal, and postmenopausal women. Day 1 of collection was the first day of menses in the cycling women. RESULTS: Postmenopausal women exhibited a widely fluctuating pattern of LH beta core fragment excretion, which is not correlated with hLH measured by immunofluorometric assay or with follicle-stimulating hormone measured by immunofluorometric assay. The postmenopausal group was easily distinguished from premenopausal women on the basis of an area-under-the-curve concentration function. Perimenopausal women displayed intermediate hLH beta cf concentrations; some clearly were in postmenopausal ranges, and others were in the premenopausal ranges. CONCLUSIONS: The pattern of excretion and concentrations of the hLH beta cf is significantly different between premenopausal and postmenopausal women. Perimenopausal women exhibited intermediate changes. The capability to measure this type of stable urinary metabolite as a reflection of changes in dynamics of its parent circulating hormone offers new possibilities in the development and application of large-scale testing that does not require blood sampling.

Adult↗
PubMed1999

A trans-activation domain in yeast heat shock transcription factor is essential for cell cycle progression during stress.

Gene expression in response to heat shock is mediated by the heat shock transcription factor (HSF), which in yeast harbors both amino- and carboxyl-terminal transcriptional activation domains. Yeast cells bearing a truncated form of HSF in which the carboxyl-terminal transcriptional activation domain has been deleted [HSF(1-583)] are temperature sensitive for growth at 37 degreesC, demonstrating a requirement for this domain for sustained viability during thermal stress. Here we demonstrate that HSF(1-583) cells undergo reversible cell cycle arrest at 37 degreesC in the G2/M phase of the cell cycle and exhibit marked reduction in levels of the molecular chaperone Hsp90. As in higher eukaryotes, yeast possesses two nearly identical isoforms of Hsp90: one constitutively expressed and one highly heat inducible. When expressed at physiological levels in HSF(1-583) cells, the inducible Hsp90 isoform encoded by HSP82 more efficiently suppressed the temperature sensitivity of this strain than the constitutively expressed gene HSC82, suggesting that different functional roles may exist for these chaperones. Consistent with a defect in Hsp90 production, HSF(1-583) cells also exhibited hypersensitivity to the Hsp90-binding ansamycin antibiotic geldanamycin. Depletion of Hsp90 from yeast cells wild type for HSF results in cell cycle arrest in both G1/S and G2/M phases, suggesting a complex requirement for chaperone function in mitotic division during stress.

Antibiotics, Antineoplastic↗
PubMed1999

Total-body irradiation and melphalan is a safe and effective conditioning regimen for autologous bone marrow transplantation in children with acute myeloid leukemia in first remission. The Italian Association for Pediatric Hematology and Oncology-Bone Marrow Transplantation Group.

PURPOSE: To evaluate the safety and efficacy of a preparative regimen consisting of fractionated total-body radiation (9.9 to 12 Gy) and melphalan (140 mg/m(2) in a single dose) in children with acute myeloid leukemia in first complete remission (CR) given autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Fifty-three children (30 males and 23 females; age range, 1.5 to 18 years) were enrolled onto the study. The median time from first CR to ABMT was 3.5 months (range, 1.4 to 13 months), with 45 patients (85%) undergoing transplantation within 6 months from the diagnosis. Forty-five patients received in vitro marrow purging with standard-dose mafosfamide (100 microg/mL), seven patients were treated with interleukin-2 before marrow collection, and in the remaining child, the marrow was unmanipulated. The median infused cell dose was 1.8 x 10(8)/kg (range, 0.4 to 5.8 x 10(8)/kg). RESULTS: All patients but one achieved hematopoietic engraftment, with a median time to neutrophil recovery of 24 days (range,11 to 66 days). Treatment-related toxicity was moderate and consisted mainly of mucositis. One patient died from cytomegalovirus interstitial pneumonia, and one died from pulmonary hemorrhage. Fourteen patients (26%) relapsed at a median time of 6 months after ABMT (range, 2 to 17 months), with a cumulative relapse probability of 29% (95% confidence interval, 16% to 42%). The 5-year Kaplan-Meier estimate of survival for all 53 patients was 78% (range, 65% to 90%), whereas the overall 5-year disease-free survival was 68% (range, 55% to 81%), with a median follow-up duration of 40 months (range, 7 to 130 months). CONCLUSIONS: These data suggest that, in our cohort of patients, the combination of total-body irradiation and melphalan is safe and associated with good antileukemia activity, making ABMT an appealing alternative for postremission therapy in children with acute myeloid leukemia in first CR.

Antineoplastic Agents, Alkylating↗