Biomedical subjects

F Cicchetti

Publications and source records attributed to F Cicchetti.

35 records · Page 2Linked to original sources

PubMed1995

Calretinin-immunoreactive neurons in the human striatum.

The human striatum contains two types of neurons displaying immunoreactivity for the calcium-binding protein calretinin (CR): (1) large (22, 44 microns>), multipolar neurons with 5-7 long, aspiny and tightly branched dendrites, and (2) medium-sized (9-18 microns), round-to-oval neurons with 2-3 long, varicose and poorly branched dendrites. These CR neurons represent only a small proportion of the total neuronal population and they are heterogeneously distributed in the striatum. The large CR neurons are more numerous in the putamen than in the caudate nucleus, whereas the inverse is true for the medium-sized CR neurons. The ratio of large- to medium-size CR neurons is 1:4 in the putamen compared to 1:6 in the caudate nucleus. The existence of these two distinct subsets of chemospecific striatal neurons suggest that CR may play an important role in the intrinsic organization of the human striatum.

Adult↗

PubMed1994

Immunochemical identification of abnormal constituents in the dermis of pseudoxanthoma elasticum patients.

Pseudoxanthoma elasticum (PXE) is a connective tissue inherited disease characterized by dermal alterations and mineralization of the elastin fibres. To investigate its pathogenesis, which is still unknown, antibodies against the principal connective tissue components were assayed on ultrathin sections of dermis from 7 PXE subjects and 5 age matched controls. Both control and PXE elastin fibres were positive for heparan, dermatan and chondroitin 0-sulphates, decorin and biglycan. In PXE, elastin fibres were also highly positive for chondroitin 6-sulphate, vitronectin, fibronectin and serum amyloid antigen. Vitronectin and fibronectin were mostly concentrated in the areas of dense mineralization within the elastin fibres. The abnormal microfilament aggregates, often seen in PXE dermis, were positive for all the above mentioned molecular species as well as for collagen types I and III and fibrillin; on the contrary, they were always negative for elastin. The results suggest that PXE is a complex disorder, in which the whole extracellular matrix is deeply disturbed. Therefore, without excluding an elastin gene defect, the data seem rather to suggest that PXE is a disorder of the mechanisms controlling the production of matrix constituents and that elastin mineralization is caused by molecules abnormally produced and entrapped within the fibre during elastin fibrogenesis.

Actin Cytoskeleton↗

PubMed1994

Fosfomycin distribution in the lower urinary tract after administration of fosfomycin trometamol salt.

Fosfomycin trometamol (FT) is a new fosfomycin salt with pharmacokinetic characteristics allowing hypothesis of its use in the single-dose therapy of lower urinary tract infections. In this study the diffusion of fosfomycin into bladder mucosa and urine after administration of a single oral dose of FT (3 g) was evaluated in patients affected by bladder or prostatic carcinoma having to undergo surgery. The administration of FT was scheduled in order to obtain blood, urine and tissue samples, to be collected during surgical operation at different times post administration. The peak concentrations in serum and bladder mucosa were detected within 3 h and 6 h respectively. Fosfomycin concentrations in bladder mucosa proved to be higher than the MICs of the most common urinary tract pathogens for at least 36 h. In urine, fosfomycin reached concentrations markedly higher than those found in serum and bladder mucosa, antibacterial levels lasting until the 48th hour post dosing. Fosfomycin trometamol, because of its pharmacokinetic and pharmacodynamic properties, appears to be suitable for single-dose therapy of uncomplicated UTIs.

Administration, Oral↗

PubMed1993

Unilateral nephrectomy and progression of renal failure.

Extensive ablation of renal mass in experimental animals leads to progressive glomerulosclerosis and chronic renal failure (CRF). Clinical studies are far from answering the question whether patients with reduced renal mass are at risk of developing progressive CRF. The aim of our study was to examine the morphological and functional aspects of the remnant kidney in a group of patients who underwent unilateral nephrectomy for renal tuberculosis: 313 patients (161 M, 152 F) mean age 57.2 +/- 10.7, were examined after a period ranging from 13.56 to 591.2 months. All patients were on ad libitum diet. Hypertension was found in 34.19% of the patients; SBP was 155.29 +/- 19.9 mmHg and DBP was 92.74 +/- 13.07 mmHg. Estimation of renal size performed by ultrasound scanner gave the following results: length 116.78 +/- 8.99 mm; width 58.24 +/- 7.21 mm; thickness 17.88 +/- 1.96 mm. Kidney function assessed by serum creatinine levels showed a mean level of 1.28 +/- 0.53 mg%. Forty-two patients (13.41%) had serum levels > 1.5 mg% but 18 of them had nonconcomitant systemic or renal involvement. Microalbuminuria determined by RIA assay was found in 50.5% of the patients. In our group of patients renal functional impairment was low and hyperfiltration expressed as microalbuminuria does not appear to be a primary factor in the progression of renal failure.

Creatinine↗

PubMed1992

Aging of the human synovium: an in vivo and ex vivo morphological study.

Age-associated changes of the human synovium have been investigated by microarthroscopy, optical and electron microscopy, immunohistochemistry, and cytochemistry. The knee joints of nineteen 15- to 56-year-old subjects, classified as normal by inspection, were carefully examined by microarthroscopy; small synovial tissue biopsy specimens from both the suprapatellar pouch and the medial tibiofemoral gutter were taken. Microarthroscopy showed that the villi were more numerous and the vascular network and cell distribution and profiles less regular in aged individuals. These data were confirmed by scanning electron microscopy, which also showed large areas of the synovial surface devoid of cells and collagen bundles in contact with the joint cavity in aged subjects. Light and transmission electron microscopy confirmed these data and allowed evaluation of the number, distribution, shape, and internal organization of cells as well as the distribution of vessels and the organization of the extracellular matrix in the full thickness of the synovium (down to 2 mm). Particular attention was paid to synovial lining cells, among which three main phenotypes could be recognized: synthetic type (present at all ages and hypertrophied in aged subjects), macrophagelike (increasing with age), and fibroblastlike. Collagen increased with age. Further studies are needed for comprehensive understanding of age-associated changes in the human synovium.

Adolescent↗

PubMed1990

Pharmacokinetics and tissue distribution of amoxicillin plus clavulanic acid after oral administration in man.

Augmentin (875 amoxicillin and 125 mg potassium clavulanate) was administered orally to patients with chronic bronchitis. Concentrations of amoxicillin and clavulanic acid were measured in serum, sputum and urine. Peak serum levels for amoxicillin of 11.23 +/- 2.61 micrograms/ml were observed at 2 hours and for clavulanic acid of 2.55 +/- 0.54 micrograms/ml at 1 hour. After 9 hours, 50% of the amoxicillin and 39% of the clavulanic acid had been renally excreted. The peak sputum concentration of amoxicillin was 1.31 +/- 0.42 micrograms/ml at 4 hours and of clavulanate was 0.79 +/- 0.23 micrograms/ml at 2 hours. Patients awaiting surgery received an oral dose of augmentin as above. Samples of lung, tonsil, middle ear mucosa and prostate were obtained and tissue concentrations of both compounds measured. Peak levels of amoxicillin ranged from 0.87 micrograms/g (tonsil) to 2.56 micrograms/g (lung) and of clavulanic acid from 0.20 micrograms/g (prostate) to 0.56 micrograms/g (lung) between 3 and 4 hours after dosing.

Administration, Oral↗

PubMed1990

Immunocytochemical localization of proteoglycans within normal elastin fibers.

Appreciable amounts of glycosaminoglycans have been found by immunocytochemistry within mature elastin fibers of human dermis. On thin sections, elastin fibers showed antigenic sites for monoclonal antibodies recognizing the unsaturated units remaining after digestion of hyaluronic acid with Streptomyces hyaluronidase and after digestion of dermatan and chondroitin sulfates with chondroitinase ABC. Moreover, sectioned elastin fibers were positive towards antibodies raised against synthetic peptides corresponding to amino acid sequences near the N-terminus of the protein core of small matrix proteoglycans PGI and PGII, respectively (Fisher et al., J. Biol. Chem. 262, 9702-9708 (1987)). This is the first demonstration that highly hydrophylic molecules are strictly associated with normally cross-linked elastin. The presence of highly hydrated molecules within the elastin polymer could greatly influence its physiological properties and behavior in pathology.

Adolescent↗

PubMed1988

Pharmacokinetic profile of cefotetan in different clinical conditions.

The pharmacokinetic profile of cefotetan was studied in a group of hospitalized patients. The absorption of the molecule (after a single dose of 2 g/i.m.) was good and the drug was found to diffuse satisfactorily in the lungs, prostatic tissue, kidney and in the female genitalia.

Adult↗

PubMed1988

Prostatic tissue concentrations and serum levels of Myocamicin in human subjects.

The diffusion of Myocamicin in the prostatic tissue of patients undergoing prostatectomy after a single oral dose of 600 mg has been studied. The maximum concentration of antibiotic in the prostatic tissue and the serum peak are reached at the first hour with mean values respectively of 3.8 micrograms/g and 2.6 micrograms/ml. The concentrations of Myocamicin remain more elevated in the prostatic tissue compared with the serum levels, at the second, fourth and sixth hours. Myocamicin has shown itself to be an antibiotic with optimal capabilities of diffusion in the prostatic tissue, where it rapidly reaches good therapeutic concentrations.

Humans↗

PubMed1969