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Biomedical subjects

F Felici

Publications and source records attributed to F Felici.

At least 73 records · Page 4Linked to original sources
PubMed1991

Small acidic peptides are bound to E. coli DNA.

Low molecular weight peptides have been isolated by alkali extraction from deproteinized DNA of E. coli cells grown in the presence of radioactive glutamic acid or orthophosphate. The labeled peptides, purified by gel filtration chromatography on Sephadex G25 and G10, contain prevailingly glutamic acid, aspartic acid, glycine, serine and alanine. Electrophoretic studies at different pH show that some peptide fractions contain a phosphoric residue. The N-terminus of the phosphorylated peptides is apparently blocked and they were able to bind to DNA in the presence of Mg2+ ions. Moreover the acidic peptides extracted from E. coli DNA show a sharp activity in the control of lambda phage DNA transcription 'in vitro'.

Amino Acids↗
PubMed1991

Prediction of ramp traversability for wheelchair dependent individuals.

The purpose of this research was to obtain a single objective criterion that would constitute a reliable prediction of length and grade limits for ramps that can be traversed by any special category of wheelchair dependent individuals (WDI). The maximal voluntary force (MVC) is the main limiting factor of the performance of WDI, thus the force required to traverse a ramp has been established by means of a simple mechanical model. The real time course of force application during ascent was experimentally obtained. Then, a simplified law of force application was introduced in a computer simulation program of kinetics and kinematics of ascent. Inputs to the model were also the mass of the subject plus wheelchair, the initial velocity of the chair, and the ramp length. The output of the program was the force requirement for any given length/grade. When capsizing conditions were encountered the simulation ended. We tested the results thus obtained having some selected WDI successfully traversing ramps with the predicted length/grade specifications.

Architectural Accessibility↗
PubMed1991

Ramp length/grade prescriptions for wheelchair dependent individuals.

The aim of this work was to provide well defined criteria for ramp construction for wheelchair dependent individuals (WDI). Force capability was measured in a large sample (140) of WDI, who presented different levels of motor impairment. Levels of impairment were established on the basis of the answers given in a questionnaire regarding the degree of self sufficiency at home as well as outside the home and active participation in sports events. Taking into account those WDI who exhibited at least a minimal level of self-sufficiency, the following prescriptions are indicated. For a 1 metre ramp length, allowable maximal incline 15%; up to 3 metre ramp length, maximal incline 10%. The reliability of such prescriptions was confirmed by having a test ramp traversed by 43 WDI. These values are suggested as confidence limits when faced with public building accommodations. Special prescriptions could be adopted for selected populations of WDI.

Architectural Accessibility↗
PubMed1990

Seroprevalence of anti-Chlamydia trachomatis IgG in outpatients attending a sexually transmitted disease clinic in Italy.

Prevalence of anti-Chlamydia trachomatis specific IgG antibodies was evaluated in a sexually transmitted disease outpatient population composed of 741 heterosexuals, 470 males and 271 females, and of 147 homosexual-bisexual men. The prevalence rates were 60.0% in heterosexual males, 50.6% in females and 73.5% in homosexuals-bisexuals. A positive association between age and antibody prevalence was found in males. Among heterosexuals there is an increasing trend of seropositivity with number of partners during the previous year. A significant association between anti-chlamydial and anti-herpes simplex, type 2, antibodies has been demonstrated.

Adult↗
PubMed1990

Radioactivity in human milk.

A brief introduction outlines the sources of radionuclides in the environment, their diffusion and transfer to different environmental compartments and their pathways to individuals; definitions of the main quantities and measurement units used in the study are included. A review is given on published data concerning the radioactive contamination of human milk after the Chernobyl accident. The authors' investigation on breast milk contamination in Italy in the same period is discussed together with an examination of the natural radioactive content. Finally, possible future developments and prospects of the research on this issue are explored.

Accidents↗
PubMed1990

[Evoked phonomyography of the human masseter muscle].

Sounds obtained in normal man by electric stimulation of masseter muscle have been analyzed both in the domain of time and frequency. Data thus obtained have been compared with those obtained by the same technique in vastus lateralis and soleus muscles. Results suggest the feasibility of sound analysis in dentistry diagnosis.

Amplifiers, Electronic↗
PubMed1990

Cardiovascular load in off-shore sailing competition.

Blood pressure, heart rate, VO2 and lactate accumulation have been measured during the hauling of ropes that, in off shore sailing, very often implies MVC isometric effort. Measures have been taken alternatively on the boat or in laboratory with a boat simulator. It appears that energy output is moderate, lactic O2 debt not relevant and blood pressure is maintained quite unchanged due to the short duration of isometric effort. Cardiovascular load is therefore not heavy and sailing can be enlisted among aerobic recreational exercises.

Adult↗
PubMed1989

The most abundant small cytoplasmic RNA of Saccharomyces cerevisiae has an important function required for normal cell growth.

The most abundant RNA visible between 5.8S and 18S rRNA on an ethidium bromide-stained gel of total Saccharomyces cerevisiae RNA has an apparent size of about 600 nucleotides. By purifying the band and using it as a probe to screen a genomic library, we isolated and sequenced the unique gene for this RNA. The transcribed sequence, determined to be 519 nucleotides long, contains elements typical of RNA polymerase III transcription. The RNA is predominantly cytoplasmic, so we called it small cytoplasmic RNA 1 (scR1). ScR1 is neither 3'-polyadenylated nor 5'-trimethylguanosine capped. We constructed a null mutation of the gene by deleting 252 base pairs from the transcribed region. Haploid strains carrying the scr1-delta lesion grew very slowly, segregated cytoplasmic petites [( rho-]) at high frequency, and showed signs of aberrant cell division. A secondary structure model for scR1 shows some of the conserved features of the signal recognition particle 7SL RNAs.

Base Sequence↗
PubMed1988

Isolation and characterization of small phosphorylated peptides controlling transcription "in vitro" from trout testis chromatin DNA.

Low molecular weight peptides are linked to the chromatin DNA of several tissues, from which they can be dissociated by alkaline extraction. They show very high specific activity in the control of transcription "in vitro". In this work the biochemical properties of controlling transcription peptide effectors isolated from trout testis DNA are reported. The purified peptides prevailingly contain glutamic acid, serine, aspartic acid, glycine and alanine. Studies of the peptide structure by N-terminal analysis using the dansyl chloride procedure was unsuccessful, suggesting the presence of a blocked NH2 group. At the same time the active peptides cannot be digested by carboxypeptidases. The gel filtration of the chromatin peptidic fractions on Sephadex G-25, Trisacryl GF05 or Sephadex G-15 shows that the active peptides elute as a single major peak with an elution volume corresponding to a molecular weight of about 1000. The paper electrophoresis performed at different pH and ionic strength shows that the chromatin peptides are separated in two fractions. One of them is strongly acidic and migrates towards the positive pole until pH 1.9, indicating the presence of phosphoric residues which probably exert an important role in the control of transcription "in vitro". The chromatin peptides are further purified by Sephadex G-10 and high performance liquid chromatography. The amino acid analysis of the purified peptides are reported.

Amino Acids↗
PubMed1985

Lumbar spine loading during half-squat exercises.

Evaluation of the compressive load acting on the lumbar spine (L3-L4) during half-squat exercises executed with a barbell resting on the subject's shoulders was undertaken. The kinematics of the upper body segments of two male and two female subjects as well as the barbell were described using data obtained by means of an optoelectronic system (CoSTEL). L3-L4 compressive load was calculated using a model of the anatomy of the trunk musculoskeletal system. Filtered surface electromyographic trunk flexor recordings from the obliquus externus and rectus abdominis and trunk extensor erectores spinae muscles as well as measurement of the ground reaction forces were also carried out for predicted result validation. During half-squat exercises with barbell loads in the range 0.8 to 1.6 times body weight the compressive loads on the L3-L4 segment vary between 6 and 10 times body weight. Erectores spinae contraction force was predicted to be between 30 and 50% of the relevant maximal isometric force. The magnitude of trunk flexion was found to be the variable which influenced most spinal compression load.

Adult↗
PubMed1977

Suicide in the literary work of Cesare Pavese.

On the basis of an existential analysis (Daseinanalyse), the authors consider the suicide, at age 42, of Cesare Pavese, one of the most important Italian poets and writers of the post-World War II period. It is found that in his poems, his novels, and particularly his letters and diary the idea of suicide was present in his consciousness since adolescence; year by year it is possible to follow the development of his ideas and fantasies about suicide. Incapable of establishing authentic communication with others, Pavese narrowed his existential horizon to the point of being less and less capable of living in the world and projecting himself into the future. From these considerations it is concluded that Pavese's acute feeling of incapacity caused him to have lasting experiences of failure that brought him to view suicide as the only way to free himself from his own torment.

Adjustment Disorders↗
PubMedDate not supplied

Detection of hidden rhythms in surface EMG signals with a non-linear time-series tool.

The analysis of the surface electromyographic (sEMG) signal is particularly attractive because it provides relatively easy access to those physiological processes that allow the muscle to generate force and movement. In this paper, one of the possible applications of recurrence plot strategy to the analysis of sEMG is described. Recurrence Quantification Analysis (RQA) is an efficient time-series analysis tool pertaining to the class of non-linear dynamics time-domain processing. We analysed sEMG recorded on the biceps brachii during isometric contraction both at constant (CF) and non constant force (NCF). For comparison purposes, experimental data were analysed over epochs of 1 s so that the hypothesis of sEMG stationarity could be accepted. The analysis concerned one of the most widely used frequency parameters (namely the median frequency, MDF) and one parameter (i.e., the percent determinism %DET) extracted using the non-linear technique. Our main results are: (i) the gross average evaluated for all subjects on %DET data shows a comparable variation with respect to MDF throughout the course of CF experiments; (ii) %DET seems able to detect motor unit (MU) synchronisation; (iii) during non constant force experiments, %DET is more effective than MDF in detecting sEMG changes determined by brisk transients of force output.

Electromyography↗
PubMedDate not supplied

[The world of the epileptic: anthropo-phenomenological considerations].

After pointing out that in literature studies concerning the anthropo-phenomenologic aspects of the existence of subjects suffering from epilepsy are very scanty, the Authors dwell upon the opportunity of deepening this study which may allow a better knowledge of the complex problems of the patient. These problems should be neglected if only the biologic side of the disease was taken into consideration.

Epilepsy↗