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Biomedical subjects

G Ravaglia

Publications and source records attributed to G Ravaglia.

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

Effect of micronutrient status on natural killer cell immune function in healthy free-living subjects aged >/=90 y.

BACKGROUND: Natural killer (NK) cells play a role in natural immunity against tumor and infected cells. Advanced aging is associated with functional impairment of NK cells and increased susceptibility to nutritional deficiencies. OBJECTIVE: Our objective was to test whether micronutrient status affects NK cell activity in an older population. DESIGN: The relations between NK cell variables (percentage of leukocytes and cytotoxicity) and blood concentrations of selected micronutrients were studied in 62 healthy, free-living northern Italian subjects (25 men, 37 women) aged 90-106 y. Anthropometric measurements were also made. RESULTS: All subjects were well nourished according to age-specific anthropometric norms but many of them had micronutrient deficiencies. The prevalence of micronutrient deficiency was highest for selenium (in approximately 50% of both sexes), zinc (in 52% of men and 41% of women), and vitamin B-6 (in 40% of men and 59% of women), followed by vitamin A (in 16% of men and 27% of women) and vitamin E, vitamin B-12, and folate (each in <10% of both sexes). Ubiquinone-10 status was inadequate in 40% of women and 24% of men (P = 0.02). The percentage of NK cells was associated with serum zinc (men: r = 0.573, P = 0. 007; women: r = 0.373, P = 0.031) and selenium (women: r = 0.409, P = 0.018) concentrations. In women only, NK cell cytotoxicity at different effector-target cell ratios was positively associated with plasma vitamin E and ubiquinone-10 concentrations (P < 0.05). No significant associations with NK cell variables were found for the other measured nutrients. CONCLUSIONS: The results of this study strengthen the hypothesis that individual micronutrients may affect the number and function of NK cells in old age. The study also confirms the high prevalence of micronutrient deficiencies in healthy and apparently well-nourished persons aged >/=90 y.

Adult↗
PubMed2000

Body composition, sex steroids, IGF-1, and bone mineral status in aging men.

BACKGROUND: Bone loss in elderly men is associated with changes in body composition and reduced secretion of endogenous anabolizing hormones. The independent influences of body composition and endocrine factors on male bone metabolism, however, are unclear. METHODS: Bone mass density (BMD) (bone mass content [BMC, g]/projected bone area [BA, cm2]) at different skeletal sites, skeletal muscle, and body fat mass were measured by dual-energy X-ray absorptiometry in 129 men aged 20 to 95 years. Free testosterone, 17-beta-estradiol, dehydroepiandrosterone-sulfate, and insulin-like growth factor 1 (IGF-1) serum concentrations were measured. Because BMD may fail to control for differences in skeletal size, the associations of bone mass with body composition and hormones were studied by comparing BMD regression models incorporating age and knee height only with BMC regression models also incorporating BA. RESULTS: Skeletal muscle had close associations (p at least < .01) with BMD and BMC at almost all skeletal sites, but the strength of these associations was generally reduced in BMC with respect to BMD models. Weak associations (p < .05) were found in both models for fatness with femoral bone and for 17-beta-estradiol with total body and femoral bone. The association of 17-beta-estradiol with spinal bone was significant (p < .05) in the BMD but not in the BMC model. No association of BMC or BMD with androgens and IGF-1 reached significancy. CONCLUSIONS: Skeletal muscle may be more important than fatness and anabolizing hormones in preserving bone mass in elderly men. In contrast to traditional belief, estrogens may be more important than androgens and IGF-1 in male bone metabolism.

Absorptiometry, Photon↗
PubMed2000

Blood micronutrient and thyroid hormone concentrations in the oldest-old.

Several micronutrients are involved in thyroid hormone metabolism, but it is unclear whether their marginal deficits may contribute to the alterations in thyroid function observed in extreme aging. The relationships among blood concentrations of thyroid hormones and selenium, zinc, retinol, and alpha-tocopherol were studied in 44 healthy Northern Italian oldest-old subjects (age range, 90-107 yr), selected by the criteria of the SENIEUR protocol. Control groups included 44 healthy adult (age range, 20-65 yr) and 44 SENIEUR elderly (age range, 65-89 yr) subjects. Oldest-old subjects had higher TSH (P < 0.01) and lower free T3 (FT3)/freeT4 (FT4) ratio, zinc, and selenium serum values (P < 0.001) than adult and elderly control subjects. No significant difference was found for plasma retinol and a-tocopherol values. The associations between micronutrients and thyroid hormones were evaluated by multivariate analysis. In oldest-old subjects, plasma retinol was negatively associated with FT4 (P = 0.019) and TSH serum levels (P = 0.040), whereas serum zinc was positively associated with serum FT3 (P = 0.010) and FT3/FT4 ratio (P = 0.011). In younger subjects, no significant association was found among thyroid variables and micronutrients. In conclusion, blood levels of specific micronutrients are associated with serum iodothyronine levels in extreme aging.

Adult↗
PubMed2000

Development of acute psychotic disorders and HIV-1 infection.

OBJECTIVE: To gain more understanding about the relationship between human immunodeficiency virus type 1 (HIV-1) infection and new-onset psychosis, we compared clinical and immunological findings, psychiatric symptoms, global cognitive performance and, when available, computerized tomography (CT) findings between HIV-1-seropositive patients with new-onset psychosis and well-matched nonpsychotic HIV-1-seropositives. METHODS: Two groups of subjects: HIV-1-seropositives with new-onset psychosis (n = 12) and HIV-1-seropositives without psychosis (n = 15) were recruited through outpatient departments. Organic Delusional Syndrome and Organic Hallucinosis were clinically diagnosed using DSM-III-R diagnostic criteria. Of the baseline participants, twenty-two participated in the two-year follow-up examination. RESULTS: The prevalence of new-onset psychosis in HIV-1-infected subjects was 3.7 per 100 (95% C.I. = 1.6-5.7). HIV-1-seropositive persons with new-onset psychosis had more frequently a positive past psychiatric history, no antiretroviral therapy, and a lower global cognitive performance than did the nonpsychotic HIV-1-seropositives. CT was positive, showing generalized brain atrophy, in three out of nine patients. Remission of psychotic symptoms was observed only in two HIV-1-seropositive persons with new-onset psychosis. Death occurred in two psychic HIV-1-seropositives with simple loosely held delusions. Autopsy results showed that cortical sulci and ventricle size were graded as with moderate/severe enlargement. CONCLUSIONS: New-onset psychosis in HIV infected patients could raise considerable problems in deciding whether a presentation is organic or functional. An interaction of the disease or of psychologically "having" the disease with the presence of a psychotic reaction should also be considered. Interestingly, a protective effect of antiretroviral therapy for new-onset psychosis is suggested.

AIDS Dementia Complex↗
PubMed2000

Blood homocysteine and vitamin B levels are not associated with cognitive skills in healthy normally ageing subjects.

Increased plasma total homocysteine (tHcy) levels are a known risk factor for vascular disease and have been reported in association with cognitive impairment of old age. Alternatively, however, increased tHcy levels may simply be an indicator of B vitamin deficiency. We evaluated the relationship between plasma tHcy levels, serum vitamin B12 and folate levels, and the scores at a battery of neuropsychological tests in 54 healthy cognitively normal subjects aged 65 years and over. Hyperhomocysteinemia prevalence (plasma tHcy>15 micromol/L) was about 24%. In univariate analysis, vitamin B12 levels were associated with both verbal memory and visuo-spatial skills, whereas no association was found between psychometric test scores and folate levels or tHcy levels. However, none of the univariate associations of neuropsychological test scores and serum B12 vitamin levels was confirmed when adjusting for age, education and other confounding variables. In conclusion, although a relationship between homocysteine, B vitamins and poor cognitive skills in the elderly is plausible, this study does not suggests that such relationship is biologically important.

Aged↗
PubMed1999

Prevalence and severity of dementia among northern Italian centenarians.

Using diagnostic criteria from the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders, dementia was clinically diagnosed in 57 (62%) of 92 centenarians living in two northern Italian provinces. The condition was severely disabling in approximately 70% of the demented patients. Although clinically diagnosed AD accounted for 79% of dementia cases, almost one third of patients with AD had risk factors for vascular dementia, suggesting that the aging brain may be susceptible to multiple additive factors that impair cognition.

Aged↗
PubMed1999

Vitamin D, thyroid hormones and muscle mass influence natural killer (NK) innate immunity in healthy nonagenarians and centenarians.

Increasing evidence has demonstrated that the immune system closely interacts with other physiological systems, whose communications are mediated by circulating cytokines and hormones. The aim of our study was to test whether the number and cytolytic activity of NK cells in a group of relatively healthy Italian nonagenarians and centenarians were affected by the modifications of endocrine, metabolic and functional parameters that occur during ageing. Because of the extreme age of the study population, a cross-sectional analysis was performed. This study revealed that the group of oldest subjects with the highest number of NK cells and the best preserved cytolytic function also presented a preserved metabolism of thyroid hormones and vitamin D and integrity of muscle mass. In fact, the NK cell number and/or cytolytic activity of healthy subjects > 90 years old was positively associated with serum levels of vitamin D, while T3, FT4, i-PTH hormones and lean body mass were associated only with NK cell number. In conclusion, our results stress the paramount importance of nutritional evaluation in the clinical assessment of elderly people.

Activities of Daily Living↗
PubMed1999

Measurement of body fat in healthy elderly men: a comparison of methods.

BACKGROUND: Nutritional evaluation of elderly people is of great importance. Two-component methods for body composition assessment, such as anthropometry and bioelectrical impedance (BIA), are widely used in clinical practice, but their fundamental assumptions may be invalid in older people. Dual-energy X-ray absorptiometry (DXA) is a relatively new method for reliable and direct measurements of body mass in its three basic components: total body bone mineral content (TBBMC), mineral free lean tissue mass (LTM), and fat. In this study, percent body fat (%BF) estimates from anthropometry and BIA in men of various ages were compared with corresponding measurements by DXA. METHODS: Body fat percentage was estimated in 67 men aged 20-95 by anthropometric measurements (skinfold thickness, body mass index, or BMI), BIA, and DXA. Age-specific equations were used for anthropometry and BIA. Limits of agreement were calculated between DXA and the other methods. RESULTS: The equations based on BMI and BIA systematically overestimated %BF with respect to %BF measured by DXA in people of all ages. Intermethod difference between DXA and skinfold thicknesses was less marked, but in over-80-year-olds %BF predicted by skinfold measurements underestimated %BF measured by DXA. Interindividual and age-related variation in TBBMC and in fat-free mass mineralization could partly explain the intermethod differences found between DXA and the other methods. CONCLUSIONS: Because of practical constraints, anthropometry and BIA are often the only available options for body composition assessment in clinical routine; therefore, further research on the validity and improvement of these methods in older people is indicated.

Absorptiometry, Photon↗
PubMed1998

Natural immunity and bone and muscle remodelling hormones in the elderly.

Increasing evidence has demonstrated that the immune system is closely integrated with two other physiological systems: endocrine and nervous. They communicate through circulating humoral factors such as cytokines, hormones and neurotransmitters. We undertook a cross-sectional analysis in a group of elderly subjects over 90 years to demonstrate that a functional relationship exists among the number and cytolytic activities of NK cells, bone and muscle remodelling hormones, anthropometric parameters and physical ability. Peripheral blood samples collected from 62, 90-106 years-old subjects underwent biochemical (bone and muscle remodelling hormone levels) and immunological determinations (Natural Killer cell distribution and activity), anthropometric and functional assessment. Significant associations were found among NK cell number and cytolytic activity and serum concentrations of vitamin D, anthropometric parameters, while functional independence in daily activity was only associated with NK cell number. In general a high level of physical ability was correlated with preserved body stores and vitamin D levels. In conclusion, our results stress the importance of nutritional evaluation in the clinical assessment of elderly people. The magnitude of the NK immune response, which constitutes the first line of defence against infected and neoplastic cells, is best preserved in oldest-old people with the best hormonal parameters and nutritional measures.

Aged↗
PubMed1998

Splenic function in old age.

Hyposplenism has been reported in elderly people. However, from previous studies, it was not clear whether the observed alterations in splenic function were a physiologic effect of advanced age itself or a consequence of age-related diseases. As hyposplenism is believed to predispose to infections, autoimmune phenomena and thrombosis, this question is of great clinical concern. In the present study splenic function was assessed by counting the pitted red cells in 65 healthy subjects aged 50-108 years. At variance from previous studies, our study population consisted of free-living individuals carefully selected in order to exclude any underlying disease. The percentage of pitted red cells in 37 subjects over 70 years was significantly higher than in 28 younger subjects, although only 1 subject had a pitted red cell count indicating splenic hypofunction. A positive, but weak, correlation between the percentage of pitted red cells and age was also found when considering the whole population (rs = 0.273, p = 0.029). In conclusion, although slightly reduced with advancing age, splenic function seems basically to be maintained in elderly people.

Aged↗
PubMed1997

Anthropometric characteristics of healthy Italian nonagenarians and centenarians.

Available anthropometric reference values for elderly people do not include specific norms for over-90-year-old subjects despite their increasing number. In the present study, weight, height and a number of anthropometric variables related to body muscle and fat mass were collected from fifty-seven nonagenarian and forty-one centenarian healthy, non-institutionalized subjects living in an Italian area. Recumbent anthropometry was used to avoid errors associated with impaired mobility. Nonagenarians and centenarian men were taller and heavier than women of corresponding age and had a greater amount of muscle and trunk fat, whereas women showed a marked peripheral adipose distribution. Anthropometric values of both age-groups were generally lower than published norms for 70-89-year-old American and European elderly people. However, differences were less marked when comparing Italian nonagenarians and centenarians with French and British people aged 85 years and over than when comparing Italian subjects with American octogenarians and younger European elderly people. Taken together these findings suggest a dramatic loss of muscle and fat mass in over-90-year-old subjects with respect to younger elderly people. However, changes between successive generations and geographical influences cannot be excluded. The need for local and age-specific norms in nutritional assessment of over-90-year-old people is emphasized. It is also suggested that current anthropometric indices may not be reliable when evaluating the oldest elderly subjects.

Aged↗
PubMed1997

Chemoembolization versus chemotherapy in elderly patients with unresectable hepatocellular carcinoma and contrast uptake as prognostic factor.

BACKGROUND: Age is considered one of the important contraindications to surgery for hepatocellular carcinoma (HCC) in cirrhosis patients. We therefore evaluated the safety and prevalence of side effects in endoarterial therapy (EAT) in subjects aged over 65 years compared with younger treated patients. METHODS: Thirty-eight patients with HCC aged 65 years and over underwent transcatheter arterial chemoembolization (TACE) (n = 28) or intraarterial chemotherapy (IAC) (n = 10). The survival rate was calculated using Kaplan-Meier's method with respect to a control group consisting of younger treated subjects (44 TACE; 21 IAC) comparable for stage of HCC and severity of the underlying cirrhosis. RESULTS: The comparison between the two groups regarding side effects, procedure-related death, and survival did not show any difference considering the whole EAT procedure. TACE in elderly subjects reached a statistically lower outcome with respect to younger patients (p < .025) but remained statistically superior in survival versus both older and younger patients treated with IAC (p < .05, respectively). Stratifying the patients following the degree of Lipiodol uptake of tumor mass in the three groups (Group I, > 75%; Group II, 50-75%; Group III, < 50%), in the young subjects a higher probability of survival was strictly correlated to a degree of uptake over 75%, while in the elderly patients an impregnation over 50% was sufficient to obtain a satisfactory survival curve. CONCLUSIONS: EAT is a reliable and safe therapeutic option for the geriatric patient with HCC, with TACE showing a better efficacy than IAC, requiring a lesser degree of Lipiodol uptake to achieve an improvement of outcome.

Adult↗
PubMed1997

Determinants of functional status in healthy Italian nonagenarians and centenarians: a comprehensive functional assessment by the instruments of geriatric practice.

OBJECTIVE: To evaluate the physical ability and psychocognitive status of a population more than 90 years of age with regard to sociodemographic, behavioral, and biomedical variables known to affect functional status in old age. DESIGN: A survey design was used. SETTING: Emilia Romagna, Northern Italy. PARTICIPANTS: Eighty-four healthy community-dwelling subjects aged 90 to 106 years. MEASUREMENTS: Sociodemographic variables, health behavior, anthropometric indices, and serum DHEAS levels were recorded. Functional assessment was performed by instruments currently used in geriatric practice: the Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), and Activities of Daily Living (ADL) scale. A stepwise multiple regression analysis was performed. RESULTS: GDS scores correlated directly with MMSE scores and inversely with ADL severity scores. Poor education, institutionalization, sensory impairment, muscular mass loss, and lower DHEAS levels were the variables with the highest correlation to functional impairment. Smoking, alcohol consumption, and marital status were relatively unimportant. An inverse association was found between DHEAS levels and dependency scores of single ADLs (continence, mobility). CONCLUSION: Impaired cognitive and physical ability with no increase in depression prevalence was found in a sample of subjects more than 90 years of age free of major age-related disease. Muscular mass and DHEAS levels seem to play a role in maintaining physical independence. In turn, physical independence, as well as social and cultural factors, strongly affect the compliance of long-lived subjects with psychocognitive tests currently used in the clinical evaluation of younger old people, suggesting that these instruments are not reliable for screening for cognitive impairment and depression in the oldest old subjects.

Activities of Daily Living↗
PubMed1996

The relationship of dehydroepiandrosterone sulfate (DHEAS) to endocrine-metabolic parameters and functional status in the oldest-old. Results from an Italian study on healthy free-living over-ninety-year-olds.

Dehydroepiandrosterone sulfate (DHEAS), the major circulating adrenal hormone, has been suggested to have a role in many aging related diseases and perhaps in aging itself. Its precise biologic effects are still unknown, and data on healthy people over 90 yr of age are not available. We measured serum DHEAS levels in 75 healthy subjects aged 90-106 yr of both sexes and searched for correlations between DHEAS and several endocrine-metabolic parameters (serum thyroid hormones, GH-insulin-like-growth factor I (GH-IGF-I) axis, serum lipid profile, anthropometric indices of body composition) of the same subjects. The resulting data, normalized by logarithmic transformation (geometric mean at age 90-99, 551 ng/mL in men, 364 ng/mL in women; at age > 100 yr, 404 ng/mL in men, 521 ng/mL in women) resulted five-fold lower than DHEAS levels measured in a young control group (geometric mean at < 40 yr of age, 3110 ng/mL in men, 2824 ng/mL in women). In women over ninety yr, DHEAS was positively correlated with serum free triodothyronine (FT3) levels (r = 0.34, P = 0.05) and inversely with triglycerides (r = -0.45, P = 0.05). In men over 90 yr, DHEAS had positive correlations with body mass index (r = 0.41, P < 0.03) and waist-to-hip ratio (r = 0.47, P < 0.01) taken as indices of body's energy reserves (fat). To determine whether low serum DHEAS levels predict poor functional status in the very old, the Activity Daily Living (ADL) test was administered in all over-ninety subjects. Men with the highest functioning levels had the highest DHEAS levels (P < 0.03). Our data suggest that DHEAS levels may influence and/or be influenced by several endocrine and metabolic features of oldest-old people, depending on the sexual steroid milieu. DHEAS seems also to have a strong interrelation with functional activities. A favorable role for DHEAS in successful aging is proposed.

Activities of Daily Living↗
PubMed1995

The effect of defruiting at different stages of fruit development on leaf photosynthesis of "Golden Delicious" apple.

Net photosynthetic rates (A) of leaves on 11-year-old, field-grown apple trees (Malus domestica Borkh. cv. Golden Delicious) were measured after removal of fruits at four different stages of development. Defruiting decreased A by 21, 42, 27 and 7% when fruits were growing at 311, 293, 229 and 113 mg(DW) day(-1), respectively. Photosynthesis was inhibited more in the afternoon than in the morning, but it was not affected during the first 8 h after fruit removal. Inhibition of A was positively correlated with crop sink strength, but it was not correlated with fruit relative growth rate or crop load. Defruiting decreased A at saturating irradiances (PPFD > 1000 micro mol m(-2) s(-1)), but did not modify the apparent quantum yield of single leaves. These results suggest that the overall effect of defruiting on carbon fixation is negligible in dense canopies, but it may be significant in sparse canopies and in single shoots.

Journal Article↗
PubMed1995

[Acute cocaine poisoning in a body packer. Clinical case].

This report takes into consideration the complications due to "body packers" cocaine absorption. In particular we report a clinical case in which severe dysrhythmias occurred. We think an early insertion of a pacemaker able to rid ectopic focus by overdriving is essential by comparison with an effective anti-dysrhythmic therapy. We also examine the cocaine metabolites values in the patient's serum and urine.

Adult↗