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Biomedical subjects

A Nardi

Publications and source records attributed to A Nardi.

At least 37 records · Page 2Linked to original sources
PubMed1996

MK-801 neurotoxicity in male mice: histologic effects and chronic impairment in spatial learning.

Several histological and behavioral experiments were conducted to investigate the neurotoxic effects of MK-801 in male mice. Moderate subcutaneous (s.c.) doses of MK-801 (0.5 and 1.0 mg/kg) induced the formation of intracytoplasmic vacuoles in pyramidal neurons in layers III and IV of the posterior cingulate/retrosplenial (PC/RS) cortex in 50% and 100% of the mice from the two respective treatment groups. Electron microscopic analysis of the vacuoles indicated that mitochondria and endoplasmic reticulum are the cellular organelles most prominently involved in this pathomorphological change. Treating mice with a high systemic dose of MK-801 (10 mg/kg s.c. or intraperitoneal (i.p.)) caused selective, irreversible degeneration of a small number of PC/RS cortical neurons. Compared to saline controls, the acquisition performance of mice treated i.p. with 10 mg/kg MK-801 was chronically impaired on a spatial learning task (modified hole board food search task) when tested at several posttreatment intervals (up to at least 5 months), although the groups did not differ on activity or sensorimotor tests conducted 2 weeks posttreatment. In summary, MK-801 caused histopathological changes in the mouse brain similar to those observed in the rat. Furthermore, high dose MK-801 treatment that killed a small number of mouse PC/RS cortical neurons resulted in a chronic acquisition impairment in spatial learning, an effect not previously demonstrated in any species.

Animals↗
PubMed1996

Acute behavioral effects of MK-801 in the mouse.

The acute effects of 0.05 mg/kg MK-801 on spatial learning and memory in male mice were studied using a modified hole board food search task. Dose-response sensorimotor and activity tests suggested that this dose of MK-801 did not induce significant nonassociative effects. Mice were trained on the hole board using a massed trials protocol to learn the location of a hole baited with a food reward among four corner holes. Retention was tested 24 h later. Mice were split into two groups matched according to acquisition scores. The following week, mice injected with 0.05 mg/kg MK-801 30 min before being trained to a different baited hole were significantly impaired in acquiring a new baited hole location compared to saline-treated mice, although retention performance was unaffected. The same result was found in another experiment in which treatments were crossed over, and a different version of the task was used. However, in another experiment, 0.05 mg/kg MK-801 did not impair performance when the hole board task was well learned.

Animals↗
PubMed1995

Different rates of forearm bone loss in healthy women with early or late menopause.

The aim of this study was to evaluate whether healthy women with early or late menopause have different rates of age- and menopause-related bone loss, and whether premature menopause really represents a risk factor for osteopenia. Healthy women aged from 27 to 84 years (n = 2204), with no history of fractures, were divided into two groups according to their age at menopause (AAM): group A with AAM < or = 43, and group B with AAM > or = 50 years. Bone mineral density (BMD) was measured in the distal non-dominant forearm by single-photon absorptiometry. Group B had a significantly lower average BMD than group A (group A, 0.430 +/- 0.074 g/cm2; group B, 0.419 +/- 0.081; p = 0.003); however, the average age of group A was significantly lower, and weight and height were significantly higher. When women older than 50 years of age were divided into five age-matched subgroups, BMD was significantly lower in women with AAM < or = 43 years up to 60 years; after that age this difference disappeared and, in the oldest subgroups, BMD was significantly lower in group B than in group A. Independent variables such as age, AAM and body mass index (BMI) explain about 30% of the variation of BMD, using a multiple linear regression analysis. In both groups age and BMI weighted more than AAM in determining BMD. When BMD was plotted versus either chronological age or years since menopause, women with late menopause showed a significantly faster bone loss than those with early menopause.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Outcome for patients who relapse after allogeneic bone marrow transplantation for chronic myeloid leukemia. Chronic Leukemia Working Party. European Bone Marrow Transplantation Group.

We studied the clinical course of 130 chronic myeloid leukemia (CML) patients (89 males and 41 females) in the European Bone Marrow Transplantation Group (EBMT) registry who received transplants before January 1, 1988 and who subsequently had evidence of recurrent leukemia. All patients had received a pretransplant conditioning regimen including total body irradiation (TBI). The first evidence of relapse was cytogenetic only in 74 (57%) patients and hematologic in 56 (43%). The overall actuarial survival from relapse was 36% at 6 years, with a significantly higher proportion of survivors among female patients (53% v 30%; P < .002). In univariate analysis, the 6-year probability of survival was 52% for patients with cytogenetic relapse and 30% for patients relapsing in chronic phase (CP), while no patient who relapsed in advanced phase (AP or BC) survived more than 3.5 years from relapse (P < .0001). The actuarial survival of patients relapsing before 6 months, between 6 and 12 months, and later than 12 months after transplant was 27%, 26%, and 45%, respectively (P < .002). Among patients with cytogenetic relapse, partial or complete disappearance of Ph-positive cells occurred in 40% of untreated patients and in 42% of those treated with interferon (IFN). However, IFN therapy significantly delayed progression toward hematologic disease. Cytogenetic responses were observed in 25% of patients who received IFN for relapse into CP, while only one minor cytogenetic response was reported in patients on conventional chemotherapy. For patients presenting with cytogenetic relapse as well as for those in hematologic relapse, IFN therapy significantly improved the 2-year probability of survival. However, long-term survival for IFN-treated patients in either group was not different from long-term survival in comparable patients not receiving IFN therapy. Twenty-nine patients of this series underwent a second bone marrow transplant (BMT) and the projected survival at 4 years after the second transplant is 28%. In multivariate Cox regression analysis, four factors remained significantly associated with survival: disease phase at relapse (P < .0001), duration of time interval from BMT to relapse (P = .0001), interferon therapy at relapse (P = .0024), and patient sex (P = .0032). This retrospective study provides evidence that some patients who relapse after BMT may benefit from treatment with IFN; a second BMT may offer the chance of cure. Data from this analysis may be useful in designing future prospective trials on posttransplant CML relapse.

Adolescent↗
PubMed1993

Influence of aging and menopause in determining vertebral and distal forearm bone loss in adult healthy women.

In order to assess the relative influence of aging and menopause in determining the decrease of bone mass in adult women, two groups of normal subjects were examined in this retrospective, cross-sectional study. In group A, bone mineral density (BMD) was evaluated at spine (L2-L4) by dual X-ray absorptiometry (DXA) (Hologic QDR-1000); in group B, BMD was measured at the distal forearm by single photon absorptiometry (SPA) (Osteometer DT 100). Both groups were further divided into two subgroups: A1 and B1 included women with the same postmenopausal, but different chronological age; A2 and B2 included women with the same chronological, but different postmenopausal age. BMD and BMI-corrected BMD (cBMD) were plotted versus age and years since menopause, respectively. Mathematical analysis of the correlation curves between BMD and chronological age showed that the decrease of BMD is very similar at spine and forearm, and is better fitted by a quadratic function. Age-related fractional bone diminution shows a progressive increase with aging (at spine: -0.38%/year at 45 years, -0.81%/year at 50, -1.3%/year at 55 and -1.9%/year at 60. At forearm: -0.5%/year at 50 years, -1.1%/year at 55 and -1.68%/year at 60). On the other hand, menopause-related BMD decrement is very evident during the first year since menopause (at spine: -8.1%/year; at forearm: -3.4%/year), and progressively decreases, according to a logarithmic function. Ten years later, yearly diminution of BMD is below 1%/year and 0.4%/year at spine and forearm, respectively. At this time, age contributes to determine bone loss for 2/3 and menopause for 1/3.

Absorptiometry, Photon↗
PubMed1992

Micellar electrokinetic chromatographic study of hydroquinone and some of its ethers. Determination of hydroquinone in skin-toning cream.

The separation of hydroquinone and some of its ether derivatives was studied by micellar electrokinetic chromatography with sodium dodecyl sulphate as an anionic surfactant in the background electrolyte. The optimized method was used for the determination of hydroquinone in a sample of skin-toning cream. On-column detection at 254 nm with caffeine as an internal standard gave good quantitative results.

Caffeine↗
PubMed1992

Ectodermal dysplasia, ectrodactyly, clefting, anophthalmia/microphthalmia, and genitourinary anomalies: nosology of Goltz-Gorlin syndrome versus EEC syndrome.

We report on two unrelated Brazilian girls born to normal and nonconsanguineous parents and presenting ectodermal dysplasia, ectrodactyly, clefting, tear duct anomalies, and micro/anophthalmia. The clinical picture presented by these patients suggests the diagnosis of Goltz-Gorlin (Focal dermal hypoplasia) syndrome and EEC syndrome.

Abnormalities, Multiple↗
PubMed1991

Application of capillary zone electrophoresis to the characterization of multiple antigen peptides.

Capillary zone electrophoresis (CZE) was applied to the analysis of a recently described class of synthetic branched peptides, multiple antigen peptides (MAPs). In comparison with high-performance liquid chromatography (HPLC), CZE showed superior resolution of minor impurities in samples of MAPs obtained by preparative chromatography. MAPs that differed only in the substitution of uncharged residues (Ala-Ser) could be separated by the addition of organic solvents (acetonitrile, methanol, ethanol) to the aqueous background electrolyte.

Amino Acid Sequence↗
PubMed1991

Capillary zone electrophoresis and mass spectrometry for the characterization of genetic variants of human hemoglobin.

This paper describes a simple and rapid analytical method for the structural identification of abnormal human hemoglobins. Globin chains obtained by precipitation of erythrocyte hemolysate in cold acetone are directly analyzed by capillary zone electrophoresis in coated capillaries without any prior treatment. The speed and the high resolving power of capillary zone electrophoresis allow fast differentiation of hemoglobins with similar charges. Capillary zone electrophoretic tryptic mapping has also been performed for each globin, so that complete variant characterization can be achieved by direct comparison of the variant tryptic map with the corresponding normal one. Coupling electrophoretic data with analysis of enzymatic digests by mass spectrometry according to the "fast atom bombardment mapping" procedure makes it possible to quickly identify amino acid variations. This paper describes how the method can be applied to the characterization of common and uncommon variants and underlines the advantages and limitations of the procedure along with its potential uses in structural analysis of proteins.

Chromatography, High Pressure Liquid↗
PubMed1990

Capillary zone electrophoresis in pharmaceutical analysis.

The paper presents a brief characterization of capillary zone electrophoresis, a modern analytical separation method with high expediency for practical applications, especially in pharmaceutical analysis. Basic theoretical considerations are presented and discussed to explain the effects of the operational parameters upon the separation efficiency and resolution of species. Descriptions of simple instrumentation and of the analytical procedure itself are given. Experimental examples are given of the separation of mixtures of pharmaceutically important compounds and of the effects of operational parameters, especially pH of BGE and voltage applied. Lastly, the practical application of CZE for analysis of isoxsuprine in commercial preparations is shown.

Electrophoresis↗
PubMed1990

Capillary zone electrophoresis of rare earth metals with indirect UV absorbance detection.

The separation of 14 lanthanides by capillary zone electrophoresis was studied in the background electrolyte containing hydroxyisobutyric acid as complexing counter-ion and creatinine as a UV absorbing coion for indirect detection of lanthanide zones. A complete separation was achieved in less than 5 min and the applicability of the method for the analysis of real samples was demonstrated.

Creatinine↗
PubMed1989

[Protocol and feasibility of a randomized controlled study on preventing the smoking habit in adolescents].

As no similar study has been conducted in Italy, the Local Health District (USL) of Rozzano (Milano), decided to carry on a randomized controlled trial on the efficacy of a Smoking Prevention Program. In this article we describe study protocol and give data related to program steps already carried out. A team of four MDs involved in school health and a Health Research consultant were in charge for the study. 1013 students from the second class of the secondary school (12y age) were stratified into four subgroups, according to their risk of becoming a smoker and their teachers smoking status. They were subsequently randomized (with blocking) to two groups: the smoking prevention (which was based on the Waterloo Smoking Program) and the cardiovascular risk prevention (based on an ad hoc program by the USL) which was the control group. Both interventions consisted in six weekly lessons which were delivered in 37 classrooms (777 students or 61% of all the eligible student population, 72% of randomized students) by an equal number of teacher who voluntarily joined the program, during school hours. A larger number of teachers (53) formerly joined the program but not all accomplished it. Problems with program planning and delivering are described, together with the criteria which guided this approach.

Adolescent↗
PubMed1988

Radical cystectomy in bladder cancer: mortality and morbidity. A series of 123 cases.

Radical cystectomy for bladder cancer is an operation that presents a low mortality rate, which can still be reduced by a better patient selection, particularly with respect to patients presenting a high cardiac risk. Morbidity is still elevated but a better preparation of the patients against infection, hyperdiuresis during and after the operation and a nonperitonization of the anterior pelvis should reduce the frequency of abscesses, septicemia and pyelonephritis. It seems reasonable to propose this operation as a curative procedure for stage B and recurring stage A and as a palliative procedure for stages C and D.

Female↗
PubMed1986

Acute vesiculitis and its prostatic complications caused by E. coli in the rat.

Injection of solutions of E. coli leads to vesiculitis which regresses spontaneously, and to interstitial prostatitis. Castration preceding experimental injection of a bacterial solution modifies the progression of the vesiculitis which then becomes chronic. Infection does not seem to diffuse via the lympathic system, even after castration.

Acute Disease↗