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C Gatti

Publications and source records attributed to C Gatti.

At least 37 records · Page 2Linked to original sources

On the origin of topological differences between experimental and theoretical crystal charge densities

Topological analysis of experimental and theoretical (molecular and crystal) electron densities of p-nitroaniline and p-amino-p'-nitrobiphenyl reveals considerable discrepancies between experiment and theory for the bond critical points properties. Particularly large differences occur for the positive curvature along the bond path (lambda 3). The differences become somewhat smaller when more extended basis sets and correlation effects are introduced in the theoretical calculations. The effect of the crystal matrix on the properties of bond critical points is evaluated for the p-nitroaniline molecule using the 6-21G** and 6-31G** basis sets. The differences between the isolated molecule and the molecule in the crystal are too small to explain the quantitative disagreement between the theoretical and experimental topologies reported in the literature and found in the current study. For most bonds, the observed changes in the properties of the electron density agree well for both basis sets but some discrepancies are found for changes in lambda 3 for N-H and aromatic C-C bonds. When the theoretical densities are projected into the multipole density functions through refinement of the theoretical structure factors, the topological properties change and differences between theory and experiment are reduced. The main origin of the observed discrepancies is attributed to the nature of the radial functions in the experimental multipole model.

Journal Article↗

Sodium sensitivity of blood pressure in long-term detoxified alcoholics.

To investigate whether sodium sensitivity of blood pressure participates in the relationship of arterial hypertension to chronic alcohol consumption, 30 alcoholics detoxified from 6 to 12 months and 30 teetotaler controls underwent a dietary sodium manipulation study. They received a daily 55 mmol sodium diet for 7 days, followed by a 260 mmol sodium diet for 7 days. Changes in 24-hour urinary sodium excretion between the end of each period were similar in alcoholics and controls (202+/-16 SEM mmol and 227+/-11, respectively). Plasma renin activity in alcoholics was lower than in controls at both low (2.4+/-0.4 ng angiotensin I/mLxh(-1) versus 3. 7+/-0.2, P<0.003) and high sodium intake (0.47+/-0.10 versus 0. 82+/-0.10, P<0.05), with smaller variations in alcoholics (-1.9+/-0. 3 versus -2.9+/-0.2, P<0.009). In alcoholics, alteration in sodium intake was followed by greater changes in both systolic and mean blood pressure (ambulatory blood pressure monitoring), which rose by 10.6+/-2.2 mm Hg and 7.3+/-1.5 versus 4.7+/-1.4 and 3.9+/-1.0 in controls, respectively (P<0.03 for systolic and P<0.05 for mean blood pressure). The ratio of changes in mean blood pressure to those in 24-hour urinary sodium excretion was higher in alcoholics (0.044+/- 0.011 mm Hgxmmol(-1) versus 0.018+/-0.0041, P<0.005). Our data show that in detoxified alcoholics, there is an abnormal response of both blood pressure and plasma renin activity to variations in salt intake similar to that in sodium-sensitive arterial hypertension. The precise relationship between the sodium sensitivity of blood pressure in detoxified alcoholics and the long-term influence of alcohol on blood pressure remains to be elucidated.

Alcoholism↗

Persistent cloaca: are we ready for a correct prenatal diagnosis?

Cloacal malformations are rare and can present in variable aspects. The importance of ultrasound in detecting these anomalies is well known. Sonographic features vary in accordance with the type of malformation and the gestational age. A positive diagnosis is not possible because of the lack of specific ultrasound findings, which can show similar aspects to other abnormalities. We present 3 cases of prenatal diagnosis of this malformation, emphasizing that in the presence of a plurilobed cystic pelvic fetal mass with associated malformations, such as cardiac, renal, and vertebral anomalies, a persistent cloaca can reasonably be suspected.

Abnormalities, Multiple↗

Compliance with advance directives: nursing's view.

The purpose for this article is to define the terms of the Advance Directive within the legal and medical community and then to explore the bioethical implications of the Advance Directive for the nurse. Over the last decade, a legal document has entered the arena of the health care facility: the Advance Directive. Today, not only is the critical care nurse responsible for technical handling of the ever-changing medical equipment, advances in medicine and nursing, and new pharmaceuticals, but this nurse is also responsible for being ever cognizant of a very important legal document called the Advance Directive.

Advance Directives↗

Prognostic significance of vascular endothelial growth factor protein in node-negative breast carcinoma.

BACKGROUND: The clinical outcome is generally positive for patients with node-negative breast carcinoma (i.e., those who do not have detectable metastases in the lymph nodes) who have been treated with surgery or surgery plus radiation therapy. In about 30% of the patients, however, the disease recurs, and they are at risk of death. Determination of valid new prognostic indicators would improve the ability to identify patients at high risk of recurrence. Breast cancer can entail substantial development of new blood vessels within the tumor tissue, and it is known that the growth and metastasis of solid tumors are dependent on such angiogenesis. The conversion of tumor cells to an angiogenic phenotype may be preceded by a change in the balance of angiogenic growth factors and angiogenesis inhibitors. PURPOSE: This study was conducted to determine if the levels of vascular endothelial growth factor (VEGF) protein, a potent endothelial growth factor and mediator of vascular permeability and angiogenesis, measured in the primary tumors of women with node-negative breast cancer are associated with known prognostic factors and patient survival. METHODS: By use of a selective enzymatic immunoassay, levels of VEGF protein were measured in cytosolic extracts of primary tumor tissue surgically obtained from 260 women with node-negative breast carcinoma who had been treated with surgery with or without radiation therapy but not with adjuvant therapy and who had been followed for a median time of 66 months. The relationships between VEGF concentrations and other prognostic dichotomous variables or clinical outcome were tested by the use of the Kolmogorov-Smirnov test and univariate and multivariate Cox analyses, respectively. The relationship between VEGF and hormone receptors (i.e., those for estrogen and progesterone) was examined by the use of Spearman's correlation analyses. All P values resulted from the use of two-sided statistical tests. RESULTS: Tumors from 247 (95%) of the 260 patients had detectable VEGF, ranging in concentration from 5.0 to 6523 pg/mg protein (median, 126.25 pg/mg protein). No statistically significant associations were found between VEGF and the other prognostic factors (e.g., age, menopausal status, histologic tumor type, tumor size, and hormone receptors) examined. Levels of VEGF were found to be prognostic for both relapse-free and overall survival in univariate and multivariate analyses (likelihood ratio tests; all four P values < .001). In the multivariate analysis, the first-order interaction term of VEGF and estrogen receptor was also prognostic for overall survival (likelihood ratio test; P = .05). CONCLUSIONS: The results show that cytosolic levels of VEGF in tumor tissue samples are indicative of prognosis for patients with node-negative breast carcinoma.

Adult↗

Phase II study of continuous-infusion high-dose ifosfamide in advanced and/or metastatic pretreated soft tissue sarcomas.

BACKGROUND: Ifosfamide has important activity in pretreated soft tissue sarcomas (STS), and recent data support a clinically significant dose-response relationship for this agent. Administration by continuous infusion and hematopoietic support have rendered dose intensification regimens possible by reducing both hematologic and non-hematologic toxicities. The optimal dose and schedule of ifosfamide when given at high doses remain to be defined. In a previous phase I study, we demonstrated the feasibility of a continuous infusion (c.i.) high-dose ifosfamide (HDI) regimen in the ambulatory setting for patients with advanced solid tumors. The objective of the present phase II study was to assess the antitumor activity and toxicity of such a schedule in patients with advanced pretreated STS. PATIENTS AND METHODS: Thirty-eight patients with advanced and/or metastatic STS, all pretreated with an anthracycline with or without standard-dose ifosfamide, were treated. Ifosfamide was given by c.i. at a dose of 3.5 g/m2/day over four consecutive days, with equidose mesna uroprotection over five days. G-CSF was added at a dose of 200 micrograms/m2/day subcutaneously from day 6 to day 12. Cycles were repeated every three weeks in the outpatient setting. RESULTS: A total of 159 cycles of therapy were given (median 4 per patient, range 3-6). Treatment compliance was generally satisfactory. The major toxicity was hematologic, with six febrile neutropenic episodes requiring hospitalisation and parenteral antibiotics. Acute renal failure occurred in one patient after three cycles of therapy; central nervous system toxicity was mild. An overall response rate of 39% was observed (95% confidence interval, 26% to 55%), with one complete and 14 partial remissions. All but one of the responder patients had previously received standard-dose ifosfamide. The median response duration was nine months (range 5-21+ months), and the overall median survival ranged from 6-30+ months (median 13 months). CONCLUSIONS: High-dose ifosfamide is an active regimen in anthracycline-pretreated STS. Future clinical trials should be aimed at evaluating the impact of different administration schedules on clinical response and outcome. The potential role of HDI as front-line chemotherapy as well as in the adjuvant treatment of STS needs to be investigated in randomized trials.

Adult↗

Implant-retained mandibular overdentures with immediate loading. A retrospective multicenter study on 226 consecutive cases.

A multicenter retrospective study has been conducted on 226 patients necessitating an implant-supported overdenture in the lower jaw. The patients were provided with 904 osseointegrated implants inserted in the interforaminal area of the mental symphisis (4 implants per patient). 4 titanium implant systems were used: TPS and ITI screw implants (Straumann Institute, Waldenburg, Switzerland); Ha-Ti screw implants (Mathys Dental Implants, Bettlach, Switzerland); NLS screw implants (Friatec, Mannheim, Germany). Immediately after implant placement, a U-shaped gold bar was fabricated and implants were immediately loaded with an implant-retained overdenture. Out of 226 patients treated, 194 were followed from a minimum of 2 years to a maximum of 13 years, with a mean follow-up of 6.4 years, whereas 32 patients dropped out during follow-up. The overall failure rate of implants was 3.1% (24/776 implants), whereas the failure rate of bars was 1.5% (3/194 bars). Results from this study showed that the success rate of immediately loaded implants is similar to that obtained in the case of delayed loading, after osseointegration has taken place. In contrast, this method shortens dental rehabilitation times with relevant satisfaction for patients.

Adult↗

Clinical observations with a new specific assay for bone alkaline phosphatase: a cross-sectional study in osteoporotic and pagetic subjects and a longitudinal evaluation of the response to ovariectomy, estrogens, and bisphosphonates.

The purpose of this study was to examine the serum levels of bone alkaline phosphatase (BALP) measured with a new assay in normal and in osteoporotic women, and to evaluate prospectively its responsiveness to changes of bone metabolism. The following groups of subjects were studied: (1) 95 healthy women (44-75 years) (22 pre- and 73 postmenopausal) and 35 osteoporotic women [vertebral bone mineral density (BMD) more than 2.5 SD below the normal adult mean]; (2) 10 women (44-50 years) ovariectomized (OVX) for benign uterine diseases, examined before and 12 months after surgery; (3) 16 OVX women (36-54 years), examined before and after 12 months of transdermal estrogen replacement therapy (50 microg/day); (4) 12 previously untreated pagetic patients (4 women and 8 men, 50-80 years), examined before and 3 months after the I.V. administration of clodronate (600 mg) or alendronate (5 mg) for 2 consecutive days. The median BALP value was 11.6 U/liter (25-75th percentiles: 10.5-12. 7; range 7.7-19.3) in healthy premenopausal (PreMP) women and significantly higher (median: 16.8 U/liter; 25-75th percentile: 13. 8-21.8; P < 0.01) in postmenopausal (PostMP) women. There was a clear age-related increase in normal subjects (r = 0.43; P < 0.001). In the osteoporotic group, BALP levels, as well as other biochemical parameters of bone turnover, were not significantly different from those of normal women when adjusted for age. In OVX women, BALP levels showed a marked increase 12 months after surgery (median: 113%; 25-75th percentile: 87-139%), significantly higher than the increase of total ALP (median: 43%; 25-75th percentile: 25-66%; P < 0.001), and similar to the increases of serum osteocalcin and urinary hydroxyproline. Transdermal estrogen treatment prevented the BALP increase, even if no reduction was observed; total ALP showed a similar behavior. The basal levels of BALP were significantly elevated in pagetic patients (median: 91 U/liter; range 18-610 U/liter) and correlated to the scintigraphic extent of the disease (r = 0.76; P < 0.01). Three months after the I.V. administration of bisphosphonates, the decrease of BALP was more marked than that of total ALP (median: -54% versus -41%; P < 0.05). In conclusion, these results suggest that BALP measurement with this immunoassay may be clinically useful, and more sensitive than total ALP, in the assessment of bone turnover during changes of the estrogen status as well as in monitoring the effects of treatments that modify the metabolic activity of the skeleton.

Adult↗

Influence of nitric oxide on hypoglycemia--or angiotensin II-stimulated ACTH and GH secretion in normal men.

In order to establish whether nitric oxide (NO) is involved in the regulation of ACTH and/or GH secretion, normal male subjects were treated i.v. with the NO-synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME) (40 micrograms/kg injected plus 50 micrograms/kg infused over 60 min) in basal conditions and/or during stimulation with insulin (0.15 IU/kg body weight in an i.v. bolus) to induce hypoglycemia (ITT) or ASP 1 ILE-5 angiotensin II (ANG II) (increasing doses of 4, 8 and 16 ng/kg/min, each dose for 20 min). The administration of L-NAME neither changed the basal secretion of ACTH and GH nor modified the hormonal responses to ANG II stimulation. Also the GH response during ITT remained unchanged in the presence of L-NAME. In contrast, the ACTH response to hypoglycemia was significantly higher when L-NAME was administered. These data suggest that in normal men NO has a negative effect on ACTH secretion, but not GH secretion, in response to hypoglycemia. Furthermore, our results argue against a role of NO in the control of basal and ANG II-stimulated ACTH and GH secretions.

Adrenocorticotropic Hormone↗

Acute effects of bisphosphonates on new and traditional markers of bone resorption.

Bisphosphonates are known to be potent inhibitors of osteoclast activity and their only clinically relevant effect in the short-term is the selective inhibition of bone resorption. The purpose of this study was to compare the response to the intravenous administration of two bisphosphonates, clodronate and alendronate, of several biochemical markers of bone resorption, including tartrate-resistant acid phosphatase (TRAP) and cross-linked carboxyterminal telopeptide of collagen I (ICTP) in serum and hydroxyproline (OHP), free pyridinium cross-links (Pyr), and cross-linked N-telopeptides of collagen I (NTx) in urine. The study was carried out on 11 osteoporotic and 12 Pagetic subjects of both sexes, treated with clodronate (600 mg/day for 2 days) or alendronate (5 mg/day for 2 days), and monitored for 28 days after bisphosphonate administration. All the urinary markers of bone resorption showed a prompt decline after bisphosphonates, with maximum reductions after 7-14 days: Pyr decreased by 43% +/- 9% and 42% +/- 22% (mean +/- SD), respectively in osteoporotic and pagetic subjects, OHP by 51% +/- 14% and 51% +/- 20%, and NTx by 55% +/- 15% and 65% +/- 26%. In the osteoporotic group, the urinary markers began to increase again at 30 days, though still remaining well below the basal level, whereas in the pagetic group, the excretion of all markers remained depressed until the end of the observation period. The reduction of NTx was significantly greater than that of Pyr and OHP in pagetic patients (P < 0.05) and tended to be greater than that of Pyr in osteoporotic patients (p = 0.07).(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Phosphatase↗

Anti-HBV neonatal immunization with recombinant vaccine. Part II. Molecular basis of the impaired alloreactivity.

HLA study was performed in 9 absolute non-responder (serum titre of anti-HBsAg < 2 mIU ml-1) and 8 hyporesponder (serum antibody level between 2 and 9.9 mIU ml-1) babies who underwent, in neonatal period, HBV vaccination with Engerix B recombinant vaccine. The investigation pointed out that many of these subjects carry HLA haplotypes classically involved in autoimmune diseases: namely HLADR7; DQ2, DR4; DQ8 and DR3; DQ2. The genomic typing for DRB1, DRB3, DRB4, DRB5, DQA1, DQB1 and DPB1 genes revealed an increased frequency of the DRB1*0701; DQA1*0201; DQB1*0201 haplotype (23.5 vs 9.9% of the controls) and of DPB*0201 allele (42.3 vs 13.2% of controls). The polymorphism of Bf, C4A and C4B complement serum components, recognized as important "immune-function-related genes", pointed out an increased frequency of the null allele C4AQ0 (34.3 vs 6.8% of the controls) stressing the role of C4A serum complement component in response to foreign peptide. The immunogenetic investigation has been extended to 23 responder babies (titre of anti-HBsAg > 50 mIU ml-1), vaccinated with the same trial as the poor responders. The HLA frequencies observed in this group were comparable to those of control population and, with respect to the HLA markers cited above, absolutely different from the non/hyporesponder infants. From the HLA class II sequence analysis in the group of poor-responder babies some characteristics, peculiar to autoimmune diseases, have been observed: the majority of the infants showed at least an arginine at the 52 residue of the alpha chain of DQ molecule and a non-aspartic acid at the 57 position of the DQ beta chain.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗

Scintigraphic assessment of pituitary adenomas and several diseases by indium-111-pentetreotide.

The aim of this study was to identify the specific somatostatin receptors expressed by several tumors, utilizing 111In-octreotide, a long acting somatostatin analogue. We studied two different groups of patients: the first group was composed of 21 patients suffering from different pituitary adenomas, while the second group consisted of 12 patients affected by several different neoplasms. In vivo scintigraphy showed pentetreotide receptors only in large GH-secreting adenomas and several macroadenomas. Concerning the endocrine activity of the adenomas, 111In-octreotide showed a good sensibility in detecting GH-secreting tumors. In the second group, 111In-octeotride proved to be a good diagnostic tool to show carcinoid lesions which were missed by other complementary methodologies.

Adenoma↗

PS2 in breast cancer--alternative or complementary tool to steroid receptor status? Evaluation of 446 cases.

The oestrogen induced pS2 protein was measured in the cytosol of 446 breast cancer samples by an immunoradiometric assay. The relationships between pS2 and several clinical and biological parameters were evaluated. pS2 was not correlated to age, pT and nodal status, while it was higher in pre- than in peri- and post-menopausal women. A statistically significant positive association was found between pS2 and ER, PgR and cathepsin D. However, the frequency of pS2 negative values in ER+ (25.6%), PgR+ (21.7%) and cathepsin D-(19.0%) cases suggests that pS2 provides information independent of the above parameters in a fairly high percentage of patients. The prognostic role of pS2 was evaluated in 267 cases (follow up time 24-102 months). pS2+ showed longer RFS (P = 0.016) and OS (P = 0.004) than pS2-. pS2+ cases were significantly associated with a better prognosis in N+ but not in N- cases. Multivariate analysis showed that pS2 is an independent prognostic factor being the second most effective indicator for OS after nodal status and the third for RFS after nodal status and cathepsin D. From the present findings, we conclude that pS2 probably provides additional biological information to steroid receptor status and cathepsin D in patients with primary breast cancer.

Adult↗