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M Cesari

Publications and source records attributed to M Cesari.

At least 37 records · Page 2Linked to original sources
PubMed2000

Are fasting plasma homocyst(e)ine levels heritable? A study of normotensive twins.

BACKGROUND: Plasma homocyst(e)ine levels (pHo) can be a risk marker for cardiovascular diseases. Different factors affect pHo, but it remains unclear whether pHo are genetically determined and whether they are related to other risk markers, such as the angiotensin I converting enzyme (ACE) and the plasminogen activator inhibitor type-1 (PAI-1). METHODS: We measured fasting pHo, plasma levels of ACE (pACE), and PAI-1 antigen (PAI-1:ag) in 60 pairs of healthy monozygotic (MZ) and dizygotic (DZ) normotensive twins. Twin zygosity was determined with polymerase chain reaction analysis of informative minisatellite markers. pHo data were first analyzed with TWINAN90 to obtain estimates of genetic variance and heritability and then examined jointly in a path analysis. RESULTS: Thirty-one twins were MZ and 29 DZ. The mean pHo were 10.48 +/- 4.07 mumol/L (95% confidence interval, 9.73-11.24 mumol/L). Two pairs had to be excluded from further analysis because of overt hyperhomocyst(e)inemia resulting from concomitant drug treatment. Highly statistically significant intraclass correlation coefficients were observed both in MZ (r = 0.421; P = 0.008) and in DZ (r = 0.488; P = 0.004). Because all tests of genetic variance and heritability were not significant, the hypothesis of genetic variance and heritability of pHo was rejected. The preferred model of a likelihood-based analysis included an additive genetic influence (A), a common environmental influence (C), and an individually unique environmental influence (E), accounting for 8%, 39%, and 53%, of pHo variance, respectively. No relationship between pHo and pACE or PAI-1:ag was detected. CONCLUSIONS: These data do not support the contention that normal-to-borderline elevated pHo of healthy subjects are heritable and under major genetic influence. They suggest that E and C are far more important than A in determining pHo variance. Furthermore, they provide no evidence of a relationship of pHo with pACE and PAI-1:ag.

Adult↗
PubMed1999

Interactions between endothelin-1 and the renin-angiotensin-aldosterone system.

The renin-angiotensin-aldosterone (RAA) system and the endothelin (ET) system entail the most potent vasopressor mechanisms identified to date. Although they were studied in depth in relation to arterial hypertension and cardiovascular diseases, limited information on their interrelationships in causing hypertension and related target organ damage exists. The identification of consensus sequences for jun in the regulatory region of the preproendothelin-1 (ppET-1) gene raised the possibility of its transcriptional regulation by angiotensin II (Ang II). This was confirmed by the finding that stimulation with Ang II of cultured vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) induced expression of the ppET-1 gene and synthesis of ET-1. Endogenously produced ET-1 was found to contribute to the hypertrophic response of cardiomyocytes to Ang II and thereby to cardiac hypertrophy. Furthermore, ET-1 exerts multifaceted effects on the RAA system, such as dose-dependent inhibition of renin synthesis, and stimulation of aldosterone secretion. The finding of abundant specific ET-1 receptors in the adrenocortical zona glomerulosa (ZG) suggested a direct secretagogue effect of ET-1. In rats, ETB receptors mediate such an effect, whilst in humans, both ETA and ETB receptor subtypes intervene in regulating the transcription of the aldosterone synthase gene. In addition, ET-1 stimulates DNA synthesis and proliferation of ZG cells via ETA receptors and, therefore, might play a role in cell turnover of the normal adrenal cortex and in the onset of adrenal tumours. Studies on the in vivo interactions between ETs and the RAA system have given conflicting results, insofar as some suggested a participation of ET-1 in the pressor and cellular effects of exogenously administered Ang II, whereas others did not in the transgenic TGR(Ren 2m)27 rats and in the two-kidney, one clip.

Aldosterone↗
PubMed1999

In vivo analysis of HLA-DQ gene expression in heterozygous cell lines.

Regulation of HLA-DQ gene transcription is a complex phenomenon because the allelic polymorphism associated with these genes and their promoters is a putative source of differential allele expression. Both transcriptional and post-transcriptional regulation could account for the density of the molecules expressed at the cell surface and then for the specificity of the immune response. Different methods have been developed to evaluate the functional consequences of this polymorphism, but at present no universal method allows measurement of either the steady-state level or the half-life time of mRNA species of both DQA1 and DQB1 polymorphic genes in heterozygous cell lines. Here, we propose a potent method, based on relative quantification of reverse transcriptase-polymerase chain reaction products, which analyzes the differential expression of all DQA1 or DQB1 allele combinations. This method is used to analyze the differential expression of HLA-DQB1*020110402 alleles in the human heterozygous lymphoblastoid B-cell line. Nucleotidic sequences of the proximal upstream regulatory region of these alleles exhibit significant differences. We show that the DQB1*0402 promoter is able to mediate a transcription strength twice as efficiently as *0201. In addition, the *0402 mRNA steady-state level is also governed by a remarkable post-transcriptional regulation. Indeed, an important part (20%) of the *0402 primary transcript is derived by alternative splicing in a short mRNA translated into a nonfunctional protein. Despite their variable sequence and length, no difference in the half-life of DQB1*0201 and both DQB*0402 mRNAs was observed in B-lymphoblastoid cells. The implications of these findings are discussed.

Alleles↗
PubMed1999

Purification and characterization of a multienzymatic complex in sugarcane, a C4 plant.

We have discovered a multienzymatic complex in fresh young sugarcane leaves. This complex is constituted of three enzymes: PEPcase, NADP-MDH and malic enzyme. After successive molecular sieving chromatography, we have obtained a highly purified sample of the complex which has a molecular weight of 711 kDa. Its functional interest has been evaluated by comparing the kinetic properties of the enzymes in their free forms to those in their complexed form. We show that the association of the three enzymes leads to important changes in their respective kinetic properties.

Chromatography↗
PubMed1999

Prospective evaluation of high-dose ifosfamide-related nephrotoxicity in young adult patients with recurrent osteosarcoma previously treated with cisplatin, methotrexate and standard-dose ifosfamide.

A prospective evaluation of high-dose ifosfamide (IFO)-related nephrotoxicity in adults and young adults previously treated with cisplatin, methotrexate (MTX) and standard-dose IFO was performed. Eighteen patients (median age 22) with recurrent osteosarcoma were studied: 11 were pretreated with MTX, cisplatin and standard-dose IFO, and seven with MTX and cisplatin. The treatment was comprised of four cycles of high-dose IFO (15 g/m2 over 5 days CI) and mesna at equivalent dose with granulocyte colony stimulating factor support. Renal function was assessed before treatment, after each IFO cycle and after chemotherapy completion. Acute nephrotubular damage was always observed after each IFO cycle with significant changes of renal tubular enzymes N-acetyl-beta-D-glucosaminidase, alanine aminipeptidase, urinary excretion and reduction of tubular reabsorption of phosphate. The appearance of glycosuria was related to the cumulative dose received. Transient and reversible renal tubular acidosis was observed in three patients. WHO grade I renal toxicity was observed in two patients. After chemotherapy completion, persistent mild glomerular and nephrotubular impairment was observed in one patient who had also received aminoglycoside antibiotics due to febrile neutropenia. Persistent and mild glycosuria was documented in another patient. No significant changes compared to baseline values were observed in the remaining patients. We conclude that a chemotherapy regimen with high-dose IFO in young adults pretreated with MTX, cisplatin and standard-dose IFO is feasible with a mild, usually reversible, nephrotoxicity.

Adolescent↗
PubMed1999

Genetic determinants of plasma ACE and renin activity in young normotensive twins.

OBJECTIVE: We investigated the determinants of plasma renin activity (PRA) and plasma levels of angiotensin-converting enzyme (pACE), including the effect of the D/I polymorphism of the angiotensin-converting enzyme (ACE) gene, in monozygotic (MZ) and dizygotic (DZ) twins. METHODS: Sixty-nine pairs of twins underwent measurements of blood pressure, pACE and ACE D/I genotyping. In addition, in 30 pairs ambulatory blood pressure (ABP) monitoring was carried out. To ascertain twin's zygosity, some highly discriminating variable number of tandem repeats micro- and mini-satellite systems were analysed by polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis and silver staining. The D/I polymorphism was assessed by PCR; pACE was measured in triplicate with a colorimetric assay, and PRA by a commercial kit. In DZ twins, identity by descent of the D/I alleles was examined by PCR amplification of a highly polymorphic simple sequence repeat at the human growth hormone gene. RESULTS: pACE levels were significantly (P < 0.01) higher in DD (9.27 +/- 2.60 IU/l, mean +/-SD) than in II (6.68 +/- 3.0), with DI having intermediate levels (7.93 +/- 2.7). No difference of PRA between different D/I genotypes was found. Twin data analysis showed a statistically significant heritability of pACE, but not of PRA. No differences between MZ and DZ twins in PRA, pACE and the relationship of the D/I genotype with pACE was found. Besides showing that the D/I genotype was the most important predictor of pACE, a multivariate analysis demonstrated that identity by descent of the D/I allele, as assessed by growth hormone (GH) genotyping, also significantly affected pACE. CONCLUSIONS: In this study of normotensive twins, pACE and not PRA showed significant heritability, the former being tightly associated with the D/I ACE gene polymorphism, and/or with a quantitative trait locus in linkage disequilibrium with it.

Adult↗
PubMed1999

Determinants of plasma levels of plasminogen activator inhibitor-1 : A study of normotensive twins.

We investigated whether plasma levels of the plasminogen activator inhibitor type 1 antigen (PAI-1:Ag) are genetically determined in monozygotic (MZ) and dizygotic (DZ) twins. Twenty-five pairs of healthy twins underwent measurements of PAI-1:Ag and other variables, including body mass index, mean blood pressure, plasma renin activity, insulin, and glucose. To ascertain the zygosity of twins, highly discriminating micro- and minisatellite systems with variable numbers of tandem repeats were analyzed by PCR amplification followed by polyacrylamide gel electrophoresis. Subjects were also genotyped for the 4G/5G polymorphism by PCR. Estimates of genetic variance and heritability were obtained for PAI-1:Ag, and for body mass index, mean blood pressure, plasma renin activity, glucose, and insulin by jointly examining data in a path analysis with TWINAN90. Results showed that 12 pairs of twins were MZ and 13 were DZ. All tests of genetic variance [within pair (WP): F=6.24, P=0.002; among component (AC): F=2.62, P=0.04; average absolute difference t test=3. 00, P=0.004] showed significant genetic variance of PAI-1:Ag, but not of the other variables. Three tests of heritability (WP=0.837, P=0.002; AC=1.791, P<0.05; intraclass correlation: 1.180, P=0.001) consistently showed significant PAI-1:Ag heritability. Additive genetic influences (A), dominance genetic effect (D), and random environmental influences (E) accounted for 0.714, 0.154, and 0.132 of PAI-1:Ag variance, respectively. No effect of different 4G/5G genotypes was found. Thus, these results show significant genetic variance and heritability of PAI-1:Ag and suggest that A is more important than both D and E in determining PAI-1:Ag variance.

Adult↗
PubMed1998

S-phase-dependent action of cycloheximide in relieving chromatin-mediated general transcriptional repression.

Chromatin plays a major role in the tight regulation of gene expression and in constraining inappropriate gene activity. Replication-coupled chromatin assembly ensures maintenance of these functions of chromatin during S phase of the cell cycle. Thus treatment of cells with an inhibitor of translation, such as cycloheximide (CX), would be expected to have a dramatic effect on chromatin structure and function, essentially in S phase of the cell cycle, due to uncoupled DNA replication and chromatin assembly. In this work, we confirm this hypothesis and show that CX can induce a dramatic S-phase-dependent alteration in chromatin structure that is associated with general RNA polymerase II-dependent transcriptional activation. Using two specific RNA polymerase II-transcribed genes, we confirm the above conclusion and show that CX-mediated transcriptional activation is enhanced during the DNA replication phase of the cell cycle. Moreover, we show co-operation between an inhibitor of histone deacetylase and CX in inducing gene expression, which is again S-phase-dependent. The modest effect of CX in inducing the activity of a transiently transfected promoter shows that the presence of the promoter in an endogenous chromatin context is necessary in order to observe transcriptional activation. We therefore suggest that the uncoupled DNA replication and histone synthesis that occur after CX treatment induces a general modification of chromatin structure, and propose that this general disorganization of chromatin structure is responsible for a widespread activation of RNA polymerase II-mediated gene transcription.

Animals↗
PubMed1998

Neoadjuvant chemotherapy for extremity osteosarcoma--preliminary results of the Rizzoli's 4th study.

A neoadjuvant chemotherapy protocol (1/93-1/95) for extremity osteosarcoma preoperatively using high-dose methotrexate (HDMTX) as single agent per cycle and three different combinations of other drugs (CDP/IFO,CDP/ADM,IFO/ADM) is reported. The four drugs were used postoperatively as single agents. Treatment was uniform, but suspended earlier if total necrosis was attained. An improvement was found in the results of the previous study using only IFO postoperatively, with 16/119 patients (97%) avoiding amputation, and 38 (32%) attaining complete necrosis. At a 3-year (2-4 years) mean follow-up, 92 patients (76%) remained continuously disease-free, 2 died of chemotherapy-related toxicity and 25 suffered relapse. Projected 3-year DFS also improved (75% vs. 60%; p = 0.04). Despite limb salvage, local recurrences (6.3%) and infections were few, although postoperative chemotherapy was restarted within a week. Therefore, until new effective drugs are found, expertise in using the four known drugs may improve cure rate and help to avoid amputation in almost all patients.

Adolescent↗
PubMed1998

Predictive factors of histological response to primary chemotherapy in Ewing's sarcoma.

Clinicopathologic variables associated with a good histological response to primary chemotherapy in Ewing's sarcoma are identified. The histological response to preoperative chemotherapy in 243 cases of Ewing's sarcoma treated with neoadjuvant chemotherapy was analyzed in relation to different clinicopathological features (sex and age of the patients, tumor size, serum lactate dehydrogenase (LDH) levels, tumor site) and to the type and schedule of anticancer drugs delivered preoperatively according to three consecutive chemotherapy regimens. A higher rate of good responses was achieved with the use of ifosfamide and dactinomycin in addition to a conventional three-drug VAC regimen, suggesting that these drugs should be included from the beginning in neoadjuvant regimens for the treatment of Ewing's sarcoma. The analysis of event-free survival in 158 patients with a 4-year minimum follow-up confirmed that histological response to preoperative chemotherapy is a reliable predictor of outcome in Ewing's sarcoma.

Adolescent↗
PubMed1998

Osteosarcoma of the extremities with synchronous lung metastases: long-term results in 44 patients treated with neoadjuvant chemotherapy.

Between September 1986 and September 1991, 44 patients with lung metastases originating from an osteosarcoma of an extremity were treated with: primary chemotherapy, simultaneous resection of primary and metastatic lesions (when feasible), and then further chemotherapy. After primary chemotherapy, lung metastases disappeared in 5 patients, whereas in 11 patients they remained surgically unresectable. All 16 patients received local treatment of the primary tumor only. In the remaining 28 patients simultaneous surgical treatment of the primary and the metastatic tumor was performed. The removal of metastatic lesions was complete in 25 and incomplete in 3 patients. With a median follow-up of 8 years (5.5-10.8) all 14 patients who never achieved a tumor-free status died. Of the 30 patients who achieved remission 5 (17%) remained continuously free of disease and 25 developed new metastases, associated with local recurrence in 4 cases. The 5-year overall survival for all 44 patients of the study was 14%, and the 5-year disease-free survival for the 30 patients who reached remission was 17%. These results are significantly worse than those achieved with the same chemotherapy protocol in 144 contemporary patients with localized disease at presentation (73% disease-free and 79% overall survival). We conclude that, despite aggressive chemotherapy which is successful in patients with localized disease, the prognosis remains very poor for patients with osteosarcoma of the extremities with lung metastases at presentation, and justifies the use of novel therapies.

Adolescent↗
PubMed1998

Ifosfamide and actinomycin-D, added in the induction phase to vincristine, cyclophosphamide and doxorubicin, improve histologic response and prognosis in patients with non metastatic Ewing's sarcoma of the extremity.

The role of ifosfamide as first-line chemotherapy treatment of non metastatic Ewing's sarcoma of the extremity is still under discussion. The purpose of this paper is to report the results achieved in a neoadjuvant protocol (REN-3) in which ifosfamide, added to the conventional VACA regimen, was employed since the induction phase. Induction chemotherapy consisted of vincristine, cyclophosphamide, doxorubicin, actinomycin-D and ifosfamide. After local treatment, patients received the drugs used in the induction phase and etoposide. Between November 1991 and November 1994, 61 patients with non metastatic Ewing's sarcoma of the extremity were treated. Forty-nine patients underwent surgery and 73.5% of them had a good histologic response. At a median follow-up of 60 months (range 32-76), 48 patients (79%) remained continuously disease-free. The 5-year event-free and overall survival were 77% and 87%, respectively. These results were significantly better both in terms of histologic response or event-free and overall survival than those obtained in 58 patients with non metastatic Ewing's sarcoma of the extremity treated in a previous protocol (REN-2) in which the same drugs were used, but ifosfamide was employed only in the maintenance phase. The present study suggests the importance of early use of ifosfamide in the treatment of patients with non metastatic Ewing's sarcoma of the extremity.

Adolescent↗
PubMed1998

Predictive factors for local recurrence in osteosarcoma: 540 patients with extremity tumors followed for minimum 2.5 years after neoadjuvant chemotherapy.

We investigated predictive factors for local recurrence in 540 patients with non-metastatic osteosarcoma of the extremity treated with surgery and neoadjuvant chemotherapy, between March 1983 and October 1994. The median follow-up was 7.5 (2.5-15) years. Local recurrences developed in 31 (6%) patients after a median time of 2 (0.5-7) years. Local recurrence did not correlate with patients' age and sex, histologic subtype, site and tumor volume, presence of pathologic fracture, chemotherapy regimen and type of surgery. Local recurrence-free survival (LRFS) correlated with the quality of surgical margins and response to chemotherapy: the 7-year LRFS was 97% after adequate surgical margins and 71% after inadequate surgical margins (p < 0.0001), and was 95% in good responders and 90% in poor responders (p = 0.001). Only 1 of 31 patients with local recurrence was free of disease 15 months after the last treatment, 3 were alive with uncontrolled disease and 27 died. This post-relapse outcome is significantly worse than in patients who relapsed with metastases only (25% free of disease, 0.5-9 years after the last treatment). We conclude that, in osteosarcoma of the extremity, limb-salvage procedures should be planned only when the preoperative staging indicates that it is possible to achieve adequate surgical margins. If the pathologic examination of the surgical specimen shows inadequate surgical margins, an immediate amputation should be considered, especially if the histologic response to preoperative chemotherapy was poor.

Adolescent↗
PubMed1998

[The Gullino 3-way tube for lavage and active aspiration in the treatment of post-pneumonectomy septic complications and subphrenic abscess].

(Gullino's) three-way tube consists of a large 30-35 cm long suction tube, with a diameter of 10 x 14 mm, closed at the proximal end close to which 6-8 holes have been made for suction along a 5 cm stretch. Two small tubes of equal length and with a diameter of 4-6 mm are glued or bound to the tube: one represents an air intake with a sealed opening above the suction holes; the other, used for washing, opens freely at the level of the closed proximal end of the large section tube. After a short review of the drama and disappointments in lung surgery concerning the treatment of postoperative septic complications, the authors briefly describe the advantages of the use of two-way suction drainage tubes: using air suction (Saratoga's and Shirley's model), and above all water suction, with irrigation-washing (Luizy's and Vankemmel's models). Compared to the two-way tubes, the paper then emphasises the advantages of the three-way model: using the flow of the lavage solution for the top, it is possible to obtain an improved, continuous and rapid washing and sterilisation of the pleural cavity, while suction from below serves to avoid stasis and in the event of bronchial fistula it is therefore easy to prevent broncho-pulmonary inundation. The three-way tube was used in two cases of post-pneumonectomy pyothorax, one of which was complicated by a bronchial fistula, and in a case of sub-phrenic abscess. In the treatment of pyothorax, the three-way tube must be divided into two parts: the large suction tube and the small air-intake tube, the two-way tube, and the small washing tube. The two-way tube must be positioned on the posterior axillary line in contact or nearly with the diaphragm, the small washing tube in the 1st anterior intercostal space and the patient must change decubitus with a certain rolling rhythm. Simple pyothorax may be resolved in 48 hours; bronchial fistula in 25 days and sub-phrenic abscess in 9. These are undoubtedly exceptional results, but require further confirmation.

Adenocarcinoma↗
PubMed1997

Renovascular hypertension with low-to-normal plasma renin: clinical and angiographic features.

1. Low-to-normal renin renovascular hypertension (RVH) and the accuracy of renal vein renin ratios were investigated in 129 consecutive patients referred for suspected RVH. Forty-nine had essential hypertension, 24 unilateral renoparenchymal hypertension and 56 renal artery obstruction. Of the latter, 86% were diagnosed retrospectively as RVH, based on fall in blood pressure with correction of renal ischaemia. We measured baseline, captopril-stimulated and renal vein plasma renin activity (PRA) levels, as well as several other parameters. 2. PRA was low-to-normal in 37% of the RVH patients [low-to-normal renin (LNR-) RVH group] and elevated in the remaining 63% [high-renin (HR-) RVH group]. In the LNR-RVH group, low-to-normal renin levels, by immunoreactive active renin and plasma renin concentration measurements, and a blunted response of PRA to captopril, were seen. As compared with HR-RVH, LNR-RVH patients had a longer duration of hypertension (P < 0.05), higher serum K+ (P = 0.04) and lower diastolic blood pressure (P = 0.02). However, they did not differ for the other variables, including the fall in blood pressure after correction of renal ischaemia. Although the number of bilateral stenoses was similar in the two groups, no patient in the LNR-RVH group had total renal artery occlusion compared with 53% in the HR-RVH group (P = 0.00015). The accuracy of renal vein renin indices were high enough to justify their use only in the patients with total occlusion of a renal artery. 3. Thus LNR-RVH is common in patients with longstanding hypertension without a totally occluded renal artery. Since the sensitivity of renin measurements is low, cure of hypertension would be precluded for more than one third of RVH patients, if these tests were a prerequisite for identifying RVH.

Adolescent↗