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Biomedical subjects

L Ferrucci

Publications and source records attributed to L Ferrucci.

151 records · Page 9Linked to original sources
PubMed1982

A cytological approach to the role of guanine in determining quinacrine fluorescence response in eukaryotic chromosomes.

Photooxidation is believed to preferentially remove guanine (G) residues from chromosomal DNA. G interspersion, moreover, has been hypothesized as quenching quinacrine (Q) fluorescence in cytological preparations. Hence, we used photooxidation as a tool for inducing possible changes in the Q-banding pattern of Drosophila melanogaster, Drosophila virilis, and Mus musculus metaphase chromosomes. An enhanced Q fluorescence, which was particularly evident in certain chromosomal regions, was found. This finding would support the postulated primary role of G in determining Q bands in eukaryotic chromosomes.

Animals↗
PubMed1981

Identification of chromosome markers in interphase nuclei.

The chromosome complement of the mosquito Cuilseta longiareolata (2n=6) reveals distinguishable centromeric regions and one telomere of the Y chromosome by using light-induced differentiation and autoradiographic techniques in mitotic and premeiotic interphase nuclei. The localization of these cytological markers and their spatial relationships appear to be very similar in the two types of nuclei and suggest an interphase arrangement where centromeric regions are clustered together in a chromocenter like structure, close to the nuclear membrane, with the telomeres lying on the opposite pole of the nucleus.

Animals↗
PubMed1980

Oxygen and the photodynamic action of methylene blue on fixed eukaryotic chromosomes.

In aerobic conditions, visible light irradiation of fixed eukariotic chromosomes in dilute solutions of dyes dramatically alters chromosomal structure. Our results indirectly suggest that singlet oxygen, an electronically excited and therefore reactive form of oxygen, which is produced by visible light in the presence of methylene blue, may be responsible for chromosomal alteration.

Animals↗
PubMedDate not supplied

Variable effect of comorbidity on the association of chronic cardiac failure with disability in community-dwelling older persons.

The effect of cardiac failure (CF) and comorbidity on disability in older persons was studied in a cross-sectional survey. The whole population aged 65 + years (n=652; 628 eligible) living in a small town near Florence (Italy) was enrolled. Finally, 459 individuals (73.0% of eligible) underwent a multidimensional evaluation. CF was defined as a NYHA II-IV class in the presence of an obviously abnormal ECG. Disability was assessed by the 14-item WHO scale. Comorbid conditions that had a prevalence >5% and might be considered pathophysiologically unrelated to CF were also identified. The univariate association of CF with disability was analyzed. Multivariate associations were estimated as well, by taking simultaneously into account the effect of comorbid conditions that had an independent effect on disability and were considered as either confounders or effect modifiers of that association. Prevalence of CF [6.1% in the whole study population) was higher with advancing age ( >or=75 years: 8.3 versus 65-74 years: 4.5%, odds ratio, OR: 1.93, 95% confidence interval, CI: 1.02-4.18), in the presence of hypertension (OR: 2.87, 95% CI: 1.32-6.23), and among individuals who were living alone (OR: 2.44, 95% CI: 1.10-5.56). CF was associated with a higher prevalence of disability (38.5 versus 19.5% OR 2.67, 95% CI: 1.21-5.92). Comorbidity modified the association of CF with disability following two patterns: while the independent effect of CF on the prevalence of disability was similar in the absence or in the presence of chronic obstructive pulmonary disease, hearing impairment, gastrointestinal tract disease, or osteoarthritis, such effect was much larger in the presence than in the absence of visual impairment, previous stroke, or urinary incontinence. The composite pathophysiological pathways of such different interactions are still to be elucidated.

Journal Article↗
PubMedDate not supplied

Association of muscle strength with maximum walking speed in disabled older women.

Our aim was to study the association of lower limb strength with maximum walking speed in disabled older women and to try to detect the reserve capacity threshold for maximum walking speed and the minimum strength required for walking at a speed of 1.22 m x s(-1), which is required in crossing signaled intersections. The data are from the baseline of Women's Health and Aging Study, a population-based study on causes and course of disability. Altogether, 1,002 disabled women participated in the tests, which took place at their homes. Maximum isometric hip flexion and knee extension forces were measured on both sides using a handheld dynamometer. For analytic purposes, knee extension torque/body mass ratio (KET/BM) was calculated. Maximum walking speed was measured with a stopwatch during a 4-m walk. KET/BM had a significant effect on walking speed after controlling for number of chronic conditions, balance, use of walking aid, joint pain, age, and body height and mass. A total of 42.3% of the variation in maximum walking speed was explained by these variables. The cumulative percentage distribution of KET/BM of those able to attain a maximum walking speed of 1.22 m x s(-1) (n = 148) was flat to the level of 1.1 N x m x kg(-1), after which it turned upward, indicating that the probability of attaining 1.22 m x s(-1) started to increase after that level. By using segmented linear regression analysis, 2.3 N x m x kg(-1) was found to be the cutoff point beyond which an increase in KET/BM did not correspond to an increase in maximum walking speed. Muscle strength was positively but not linearly associated with maximum walking speed. Strength testing may help to identify people close to functional thresholds and, thus, at risk of impaired walking, who would benefit most from strengthening exercises.

Activities of Daily Living↗
PubMedDate not supplied

Auditory evoked potentials (AEPs), early (BAEPs) and long latency components (LLCs) in Parkinson's disease: a 12 month follow-up study.

In 14 untreated informed patients (5 M, 9 F, mean age 62 yrs) with initial idiopathic Parkinson's disease AEPs, early (BAEPs) and long latency components (LLCs) were studied. In 10 subjects experimental session were carried out before treatment (L-Dopa plus Carbidopa, 0.25-0.50 g/die) and at 2, 6 and 12 months intervals. At the same time all patients underwent clinical assessment by Webster Rating Scale evaluation. BAEPs. The IPLs prolonged (greater than 2.5 SD) in 6 patients: in 3 the III-V, in 2 the I-V and in 1 the I-III. The absolute latencies were abnormally prolonged in 11 subjects: V wave in 4, III wave in 3, II wave in 2 and I wave in 3. The absence of one or more components were observed in 12 out of 14 patients, the most frequently absent was the II wave (12 patients). LLCs. The absolute latencies of P1 and N1 waves were prolonged respectively in 4 and in 3 subjects. The P1-N1 IPL was prolonged only in one patient. A follow-up study demonstrated transitory improvement of the AEPs previously observed abnormalities. The improvement was partially in agreement with clinical assessment.

Adult↗