PubMed Health⌕ Search

Biomedical subjects

A M Giusti

Publications and source records attributed to A M Giusti.

At least 19 recordsLinked to original sources
PubMed2003

MNA predictive value in the follow-up of geriatric patients.

OBJECTIVE: The aim of this study is to verify, in a sample of elderly subjects admitted to long-term care, the impact of malnutrition, according to the Mini Nutritional Assessment (MNA), on mortality and on the occurrence of Adverse Clinical Events in a 3-12 months follow-up study. SUBJECTS: The survey included all patients admitted to a geriatric hospital--"Villa delle Querce", Nemi (Rome, Italy)--between January 1997 and April 2000, whose nutritional status we were able to monitor for over 3 months. The study comprised 167 elderly subjects, of which 125 women (74.9%) aged 83.3 8 years (60-95 years), and 42 men (25.1%) aged 79.6 9 years with an average follow-up period of 7.5 months. METHODS: Upon admission and at every check we evaluated each subject's cognitive functions, functional status, co-morbidity, frailty, nutritional status (anthropometric and biochemical indices; MNA). During the follow-up we recorded Adverse Clinical Events. We calculated the predictive value of MNA, we correlated variations in MNA scores with variations of nutritional parameters. RESULTS: MNA's predictive ability both upon admission and upon discharge was found to be excellent. The MNA score was found to be correlated-although not to a very high degree-with variations nutritional parameters. Even more than malnutrition, a low MNA score was found to be predictive of a greater incidence of Adverse Clinical Events during hospitalisation and of higher mortality.

Aged↗
PubMed2002

Serological survey of leptospiral infection in kennelled dogs in Italy.

Two hundred and forty-five dogs were examined serologically for the presence of antibodies against different serovars of Leptospira interrogans. The dogs belonged to five different groups: group 1 was composed of clinically healthy pet dogs referred for a regular veterinary check-up visit or for vaccination; group 2 was composed of stray dogs; and groups 3, 4 and 5 were composed of dogs maintained in three different kennels which had varying standards of hygiene. Seventy-two out of the 245 dogs examined were seropositive for leptospirosis. In group 1, there were 3-4 per cent seropositive dogs; in group 2, 30.3 per cent; in group 3, 13.8 per cent; in group 4, 38.6 per cent; and in group 5, 49.2 per cent. This study demonstrates that leptospiral infection is common in dogs housed in kennels, despite most of them being vaccinated, and that crowding of animals into unsanitary quarters is associated with a high prevalence of infection. The most common infecting serovars found were bratislava and grippotyphosa, confirming recent observations that demonstrate a significant change in the epidemiology of canine leptospirosis.

Animals↗
PubMed2002

A "proportional and objective score" for the mini nutritional assessment in long-term geriatric care.

BACKGROUND: In a previous study we tested the predictive value of the Mini Nutritional Assessment (MNA) in an Italian population of frail elderly in long-term hospital care. The results of our study confirmed the MNA's excellent overall predictive value and sensitivity. Unfortunately we had a large number of false positive judgments, hence our study's low specificity, which we think was caused by two factors: 1. in most cases it was impossible to conduct a reliable subjective assessment of the patients' nutritional and health status. 2. most patients failed to respond to some of the MNA questions, which as a consequence received a "0" score. The result was an artificially low global MNA score even in well-nourished patients. OBJECTIVE AND DESIGN: We tried to neutralize the effects of the defective answers by modifying the total score and the cut-off points of the test. Thus, we: 1. replaced the subjective assessment of health and nutritional status with an objective evaluation; 2. replaced the total score of MNA with the ratio of this value with the maximum of points that each subject can obtain without including the items for which we could not have a response. Similarly, the cut-off points (17 and 24) were replaced with the ratio of these values with the maximum of points obtainable by a complete MNA (30). Patients are classified as "malnourished" below 0.56, "at risk of malnutrition" between 0.56 and 0.79, and "well-nourished" from 0.8 up. RESULTS: This way, the overall predictive value of MNA is increased from 80.3 to 85.4% and the specificity from 12.8 to 25%, whereas the sensitivity increase is modest (from 98 to 98.1%).

Activities of Daily Living↗
PubMed2001

Capillaria hepatica infection in wild brown rats (Rattus norvegicus) from the urban area of Milan, Italy.

Forty-seven wild brown rats (Rattus norvegicus) collected from the urban area of Milan (Italy) were screened for Capillaria hepatica liver infection. The liver of each rat was grossly and histologically examined for the presence of C. hepatica adults, eggs and typical C. hepatica induced lesions. In 17 rats (36%) liver lesions consistent with C. hepatica infection were detected. Grossly, white-yellow nodules of 1-5 mm in diameter were present, either scattered on the liver surface or localized in a single lobe. Histologically, granulomatous liver lesions associated with eggs and/or worms were observed. The degree of gross liver involvement was moderate in most of the positive cases (71%). About 30 cases of C. hepatica infection in humans have been documented world-wide, most of which are reported in children from 1 to 5 years of age. Our results suggest that the potential transmission of C. hepatica to children in the study area should be considered an important health issue.

Animals↗
PubMed1998

Cell membrane lipid molecular dynamics in a solenoid versus a magnetically shielded room.

The generalized polarization function of the fluorescent probe 2-dimethylamino-6-lauroylnaphthalene has been used to evaluate the lipid dynamics in Friend erythroleukemia cell membrane. The values of this function varied during the culture growth cycle, showing decreased lipid dynamics 24-48 h from the cell seeding. When the cycle occurred in a solenoid producing a magnetic field of 70 microT at 50 Hz in addition to the 45 microT DC of the earth (short-term 4-day exposure), the membrane lipid dynamics during this same time-period decreased by about 10% (P < .04). After long-term (184 days) or extremely long-term (395 days) exposure of the cells to the magnetic field, little additional variation in the membrane lipid dynamics was observed, suggesting an adaptation phenomenon. A variation of membrane lipid dynamics was also observed due to in vitro cell differentiation (P < .02). Nevertheless, the exposure of both undifferentiating and differentiating cells to a highly attenuated magnetic field in a magnetically shielded room (20 nT DC plus 2.5 pT AC) did not induce any modification of membrane lipid dynamics.

Animals↗
PubMed1998

Effects of chronic wound fluid on the structure and biological activity of becaplermin (rhPDGF-BB) and becaplermin gel.

In this study, the effects of chronic wound fluid on the structure and biological activity of becaplermin (recombinant human platelet-derived growth factor-BB [rhPDGF-BB]) were evaluated. Wound fluid was collected from 12 subjects with diabetic ulcers or pressure ulcers. Wound fluid +/- becaplermin was added to cell cultures before- and after incubation for 12 hours at 37 degrees C or after 12 hours' topical treatment. Biological activity, concentration, and immunogenicity were determined by [3H]thymidine incorporation into quiescent human foreskin fibroblasts, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis, respectively. No PDGF-BB or mitogenic activity was detected in chronic wound fluid alone. Mitogenic activity was present in post-treatment samples from becaplermin-treated subjects but not placebo-treated subjects. Exposure to chronic wound fluid for 12 hours did not alter the amount, banding pattern, or mitogenic activity of becaplermin. Biologically active becaplermin remains in wound fluid 12 hours after topical application of becaplermin gel.

Adult↗
PubMed1998

Human cell membrane oxidative damage induced by single and fractionated doses of ionizing radiation: a fluorescence spectroscopy study.

PURPOSE: To investigate the production and repair of lipid oxidative damage in two human cell lines exposed to acute and fractionated dose of ionizing radiation. Radiation dose was in the range from 0.1 to 44 Gy. MATERIALS AND METHODS: K562 and HL60 human cell lines have been used, 24 and 96 h after seeding. Membrane lipid oxidative damage has been detected by the measurement of the fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene (DPH), its polarization value and the conjugated dienes concentration. The modification of DPH decay has been previously reported to be directly related to the lipid hydroperoxide concentration. RESULTS: A modification of the DPH decay has been observed as a linear function of the logarithm of the radiation dose and only when the irradiation was performed in the presence of oxygen. The amount of the damage is related to the time after the cell medium change. By exposing the cells to fractionated radiation doses for several days (10 cGy day(-1)), the oxidative damage has been found to be cumulative. After a single acute dose, evidence of repair of the lipid oxidative damage was not obtained. CONCLUSIONS: Following a previously developed method, the membrane damage was attributed to the production of hydroperoxide residues in the lipid acyl chains with the consequence of water penetration into the external portion of the bilayer, from the aqueous environment to the position of hydroperoxides. This damage is not repaired. The results obtained by measuring the DPH fluorescence decay have been compared with those obtained using other current optical and biochemical methods. None of these techniques could detect membrane oxidative damage at doses < 10 Gy. Finally, the different sensitivity of 'young' and 'old' cells to the oxidative damage can be related to different cholesterol concentrations.

Cell Membrane↗
PubMed1998

The roles of antibody variable region hypermutation and selection in the development of the memory B-cell compartment.

Somatic hypermutation and selection of immunoglobulin (Ig) variable (V)-region genes, working in concert, appear to be essential for memory B-cell development in mammals. There has been substantial progress on the nature of the cis-acting DNA elements that regulate hypermutation. The data obtained suggest that the mechanisms of Ig gene hypermutation and transcription are intimately intertwined. While it has long been appreciated that stringent phenotypic selection forces are imposed on the somatically mutated Ig V regions generated during a T-cell dependent B-cell response, the mechanisms involved in this selection have remained enigmatic. Our studies have questioned the role of foreign antigen deposited on follicular dendritic cells in affinity-based positive selection of V regions, and have shown that this selection takes place in a "clone-autonomous" fashion. In addition, our data strongly suggest that affinity for antigen alone is not the driving force for selection of B-cell clones into the memory compartment. In contrast, we suggest that a combination of positive selection for increased foreign antigen binding, and negative selection of antibody V regions that are autoreactive at the onset of the response, or have acquired autoreactivity via hypermutation, results in the "specificity maturation" of the memory B-cell response.

Animals↗
PubMed1998

Hyperkeratosis-associated coryneform infection in severe combined immunodeficient mice.

Hyperkeratosis-associated coryneform (HAC) is a coryneform bacterium, with a biochemical profile similar to Corynebacterium bovis, that causes hyperkeratotic dermatitis in athymic nude mice. In the present study 28 severe combined immunodeficient (SCID) mice coming from six different animal facilities were submitted for bacteriological and pathological examination. HAC was isolated from 10 SCID mice belonging to two of these facilities. Two of the HAC-infected mice showed macroscopical lesions consisting in large alopecic areas, with small white flakes, involving the dorsum, flanks, neck and cheeks. Histologically, the skin of these animals was characterized by diffuse acanthosis and hyperkeratosis. In the other eight HAC-infected SCID mice no macroscopical lesions were observed but focal areas of minimal to mild acanthosis were histologically detected in five cases. These results suggest that HAC can infect SCID mice inducing skin lesions similar, although generally less severe, to those observed in nude mice with hyperkeratotic dermatitis. Our results pointed out that SCID mice may play an important role in the epidemiology of hyperkeratotic dermatitis of athymic nude mice.

Animals↗
PubMed1998

Gastric spiral bacteria in wild rats from Italy.

Forty-three wild rats (Rattus norvegicus) trapped in Milan (Italy) were examined for gastric spiral bacteria and to evaluate associated histological lesions. Spiral bacteria were histologically detected in the stomach of 10 rats (23%). The morphological features of these microorganisms, observed using both light and electron microscopy, correspond to those of Helicobacter heilmannii. Mild gastritis characterized by focal lymphoplasmacytic infiltration of the lamina propria was observed in six rats with gastric spiral bacteria. Our findings suggest a causal role of these bacteria in inducing a gastric inflammatory response.

Animals↗
PubMed1998

Pathological and in situ hybridisation findings in calves experimentally infected with bovine adenovirus type 4.

Three colostrum deprived calves were inoculated intravenously with a strain of bovine adenovirus type 4 (BAV-4) isolated from a calf with acute fibrinous enteritis. The calves were monitored clinically and submitted to post mortem examination at 5, 6 and 10 days post inoculation (p. i.) respectively. The 3 animals showed raise in temperature and diarrhoea. Acute enteritis was observed in calves submitted to post mortem examination at 5 and 6 days p. i. In these animals viral DNA was specifically detected on histological sections by an in situ hybridization (ISH) technique; BAV-4 was isolated from most of the organs and numerous adenovirus-positive endothelial cells were present in the gastrointestinal tract, mesenteric lymph nodes and liver. In the calf examined 10 days p. i. no lesions were observed and rare ISH positive cells were detected. These results indicate that in experimental conditions our strain of BAV-4 is capable to induce clinical signs and lesions similar to those reported in field cases.

Adenoviridae Infections↗
PubMed1997

Histological and immunohistochemical findings in thoracic lymph nodes of cattle with contagious bovine pleuropneumonia.

Outbreaks of contagious bovine pleuropneumonia (CBPP) were reported in Lombardy, Northern Italy, at the end of 1990. For the purpose of this study, 54 slaughtered Holstein-Friesian cows showing typical lung lesions of CBPP from which the small colony type of Mycoplasma mycoides subspecies mycoides (M. m. mycoides SC) was isolated, were selected. Thoracic lymph nodes from these animals were sampled for bacteriological, histological and immunohistochemical analysis. Acute, subacute and chronic lesions were observed in 13, 12 and 29 cases, respectively. In the 13 animals showing acute lung lesions, an increased number of macrophages was observed, especially in the subcapsular sinuses, but frequently also in the cortical and medullary sinuses of the thoracic lymph nodes; in all 13 acute cases M. m. mycoides SC antigen was detected immunohistochemically in the cytoplasm of the macrophages. In 10 out of the 12 cases with subacute lung lesions, mycoplasma antigen was observed in macrophages located in sinuses, as well as in those scattered in the lymph node parenchyma. Hyperplasia of germinal centres in follicles was observed histologically in most of the 29 cases with chronic lung lesions. In immunohistochemically labelled sections, the characteristic finding observed in 27 of the chronic cases, was the presence of a variable amount of positive material in the germinal centres. These findings demonstrate the involvement of thoracic lymph nodes in CBPP.

Animals↗
PubMed1997

Outbreaks of hyperkeratotic dermatitis of athymic nude mice in northern Italy.

Hyperkeratotic dermatitis of athymic nude mice is an infectious disease caused by a coryneform bacterium. During the spring of 1995, outbreaks of hyperkeratotic dermatitis were observed in several nude mice facilities in northern Italy. In this report we describe the clinical, histopathological and microbiological features of the disease in two different animal facilities. Affected animals showed a typical 'scaly' appearance with small white flakes of material adherent to the skin. In one of the outbreaks (facility 2) the lesions were less severe and involved only limited areas of the body. The infection spread very quickly and the morbidity reached more than 80% in a few days, while the mortality was about 1%. The lesions resolved spontaneously within 7-10 days. Histological examination of affected skin revealed orthokeratotic hyperkeratosis, acanthosis and dermal inflammatory infiltration which were more severe in mice from facility 1. In Gram-stained sections groups of rods consistent with coryneform bacteria were detectable in the keratin layers covering the epidermal surface. A coryneform bacterium, biochemically typed as Corynebacterium bovis, was isolated from 11 out of 11 mice from facility 1 and from 8 out of 11 mice from facility 2.

Animals↗
PubMed1996

Characterization of the cis-acting elements required for somatic hypermutation of murine antibody V genes using conventional transgenic and transgene homologous recombination approaches.

We have used conventional transgenic technology and a novel transgene homologous recombination pathway to investigate the cis-acting elements necessary for murine antibody V-gene somatic hypermutation. These studies show that an undefined element 3' of the IgH intronic enhancer is required for VH hypermutation. This element appears not to be the 3' alpha IgH enhancer, at least in its "minimal' form. Elements 5' of the natural VH promoter are not necessary for hypermutation, and this promoter can be replaced by a non-Ig promoter, resulting in a reduction, but not ablation of the rate of hypermutation in the adjacent VH gene. Our analyses provide no support for "gene conversion' models of hypermutation, and support models that propose a role for transcription in hypermutation over purely DNA-based models. Analysis of a CD72/kappa chimeric transgene suggests that all of the factors that influence hypermutation of kappa transgenes have yet to be defined.

Animals↗
PubMed1995

Simple protocols for typing forensic biological evidence: chemiluminescent detection for human DNA quantitation and restriction fragment length polymorphism (RFLP) analyses and manual typing of polymerase chain reaction (PCR) amplified polymorphisms.

Methods for identity testing are described that enable extraction of DNA from biological samples, determination of the quantity of human DNA, and genetic analyses of the materials using restriction fragment length polymorphism (RFLP) typing and/or amplified fragment length polymorphism (AMP-FLP) typing of PCR products. The salient features of the procedures are simplicity, manual typing, nonradioactive chemiluminescent assays or silver staining for detection, and low cost. Most application-oriented laboratories involved in forensic and/or paternity testing should be able to implement these procedures.

Base Sequence↗
PubMed1995

Cholesterol protects the phospholipid bilayer from oxidative damage.

The measurement of fluorescence lifetime distribution of 1,6-diphenyl-1,3,5-hexatriene is used for the detection of oxidative damage produced in phospholipid membranes by ionizing radiation. The recently developed method is based on the linear relationship between the width of the probe lifetime distribution and the logarithm of the dose. The molecular origin of the damage resides in the production of hydroperoxide residues at the level of acyl chains double bonds. A chemiluminescence assay was used to quantitate the amount of produced hydroperoxides. Consequences of the produced damages include an increased disorder in the upper portion of the bilayer, accompanied by the penetration of water molecules. In the presence of the physiological concentration of cholesterol in phopholipid bilayers, the amount of hydroperoxides produced by ionizing radiation is dramatically reduced. The packing effect of cholesterol in phopholipid bilayers is well recognized, as well as its influence on the reduction of water concentration in the bilayer. The dramatic reduction of hydroperoxides concentration observed when irradiation is performed in the presence of cholesterol probably originates from a steric hindrance to the radical chain reaction through the unsaturated lipids due to the presence of cholesterol.

Cholesterol↗
PubMed1995

Abrupt modifications of phospholipid bilayer properties at critical cholesterol concentrations.

The fluorescence generalized polarization (GP) of 2-dimethylamino-6-lauroylnaphthalene (Laurdan) reveals different effects of cholesterol on the phase behavior of phospholipid bilayers. Phospholipid vesicles composed of gel, liquid-crystalline, and coexisting domains of the two phases have been studied at temperatures from 1 to 65 degrees C, without cholesterol and with cholesterol concentrations of 3-50 mol %. Laurdan GP measurements show the general effect of cholesterol of increasing the molecular dynamics of the gel and of decreasing the molecular dynamics of the liquid-crystalline phase. In the liquid-crystalline phase, the increased order yields Laurdan GP values close to those obtained in the gel phase. At cholesterol concentrations > 15 mol % a phase transition cannot be detected. Using the wavelength dependence of the excitation and emission GP spectra we determine that differences between the two phospholipid phases cannot be detected. In particular, in vesicles composed of coexisting gel and liquid-crystalline phases the GP wavelength dependence characteristic of coexisting domains cannot be observed at cholesterol concentrations > or = 15 mol %. Cholesterol causes the decrease in both the polarity and the dipolar relaxation effects on the neighborhood of the fluorescent naphthalene moiety of Laurdan. Probably because of a cholesterol-induced increase in the bilayer packing, these effects do not occur continuously with the increase of cholesterol concentration in the bilayer. Cholesterol concentrations inducing higher Laurdan GP values have been determined at about 5, 10, 15, 30, and 45 mol % with respect to phospholipids. We propose that the formation of ordered molecular microdomains at critical cholesterol concentrations can explain the occurrence of the observed discontinuities.

2-Naphthylamine↗