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S Marchetti

Publications and source records attributed to S Marchetti.

35 records · Page 2Linked to original sources
PubMed2000

C-nucleoside analogues of furanfurin as ligands to A1 adenosine receptors.

Furanfurin (2-beta-D-ribofuranosylfuran-4-carboxamide) derivatives and analogues were synthesized and their affinity for adenosine receptors was determined. The agonistic behavior of furanfurin against A1 receptors is preserved only when the furan ring is substituted with isosteric pentatomic ring systems such as oxazole, thiazole or thiophene, and the carboxamide group is unsubstituted. Replacement of the hydrogen atoms of the carboxamide group with alkyl, cycloalkyl or arylalkyl groups generates compounds endowed with moderate antagonistic activity.

Adenylyl Cyclase Inhibitors↗
PubMed2000

Is ESES/CSWS a strictly age-related disorder?

OBJECTIVES: We report on a case of ESES/CSWS observed in a patient of 21 years and still persisting at the age of 25. Cases of ESES/CSWS have never been previously described in adult patients. ESES/CSWS is considered to be related to the degree of maturation of the central nervous system, and therefore strictly age-related. METHODS: Our case of ESES/CSWS was observed in a 2 1 year old woman referred for cognitive and behavioral disorders. She had previously had epileptic fits, but was seizure free at that time. The patient underwent a full-night polygraphic recording , which showed typical ESES/CSWS pattern, with a Spike-and-Wave Index >8 5%. Polysomnography was repeated 9 times in a 4 year follow-up, during which the ESES/CSWS condition persisted, despite the pharmacological treatments. The patient also underwent cerebral magnetic resonance imaging and fludeoxyglucose F 18 positron emission tomography (PET). RESULTS: The PET study revealed reduced metabolic activity within the lower gyrus of the right parietal lobe, but no significant difference between subcortical structures and cortical mantle was seen. MRI scans were normal. CONCLUSIONS: This observation suggests that ESES/CSWS might not always be an age-related condition. Sleep EEG recordings should always be performed in patients with behavioral disorders and a history of epileptic fits.

Adult↗
PubMed1999

Clinical validation of the avidin/indium-111 biotin approach for imaging infection/inflammation in orthopaedic patients.

We report here the results of a validation study of the avidin/indium-111 biotin approach in patients with skeletal lesions. This study involved 54 patients with orthopaedic conditions: 20 patients with intermediate suspected osteomyelitis of the trunk, 19 patients with infection/inflammation of prosthetic joint replacements, and 15 patients with suspected osteomyelitis of appendicular bones. Avidin (3 mg) was injected as an i.v. bolus, followed 4 h later by 111In-biotin; imaging was acquired 30 min and 16-18 h after administration of 111In-biotin. Technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO)-labelled leucocyte scintigraphy was performed in 39/54 patients. The overall sensitivity of the avidin/111In-biotin scan was 97.7% (versus 88.9% for 99mTc-HMPAO leucocyte scintigraphy). While the diagnostic performance of avidin/111In-biotin scintigraphy was similar to that of 99mTc-HMPAO leucocyte scintigraphy in patients with prosthetic joint replacements or osteomyelitis of appendicular bones, the avidin/111In-biotin approach clearly performed better than 99mTc-HMPAO leucocyte scintigraphy in patients with suspected osteomyelitis of the trunk (100% sensitivity, specificity and accuracy versus 50% sensitivity, 100% specificity and 66.7% accuracy for 99mTc-HMPAO-leucocyte scintigraphy). These results demonstrate the feasibility of the avidin/111In-biotin approach for imaging sites of infection/inflammation in the clinical setting. Although no systematic advantages of avidin/111In-biotin scintigraphy were found versus 99mTc-HMPAO leucocyte scintigraphy, the newer scintigraphic method is more practicable and involves lower biological risk for the operators.

Avidin↗
PubMed1999

[Interstitial cystitis: medical treatment].

Interstitial cystitis is a chronic disease of the bladder and its etiology is still unknown. In this article we treat the different approaches to this disease, supported by the fact that a clear therapeutic protocol doesn't exist.

Algorithms↗
PubMed1998

2'-C-Methyl analogues of selective adenosine receptor agonists: synthesis and binding studies.

2'-C-Methyl analogues of selective adenosine receptor agonists such as (R)-PIA, CPA, CCPA, NECA, and IB-MECA were synthesized in order to further investigate the subdomain that binds the ribose moiety. Binding affinities of these new compounds at A1 and A2A receptors in bovine brain membranes and at A3 in rat testis membranes were determined and compared. It was found that the 2'-C-methyl modification resulted in a decrease of the affinity, particularly at A2A and A3 receptors. When such modification was combined with N6-substitutions with groups which induce high potency and selectivity at A1 receptors, the high affinity was retained and the selectivity was increased. Thus, 2-chloro-2'-C-methyl-N6-cyclopentyladenosine (2'-Me-CCPA), which displayed a Ki value of 1.8 nM at A1 receptors, was selective for A1 vs A2A and A3 receptors by 2166- and 2777-fold, respectively, resulting in one of the most potent and A1-selective agonists so far known. In functional assay, this compound inhibited forskolin-stimulated adenylyl cyclase activity with an IC50 value of 13.1 nM, acting as a full agonist.

Adenosine↗
PubMed1998

Absence of mutations in the highest mutability region of the p53 gene in tumour-derived CHEF18 Chinese hamster cells.

A series of independent tumour-derived Chinese hamster CHEF18 cell lines was analyzed for the presence of mutations in the cDNA region (exons 5-9) of the p53 gene, where the great majority of p53 mutations of human tumours accumulate. Since the gene is highly conserved among species, we used two primers designed on the basis of the human cDNA sequence to isolate the cDNA region from total RNA of Chinese hamster cells. The amplified fragments of 614 bp were digested with cleavase I endonuclease and fragment length polymorphism analysis showed that the restriction pattern of the p53 exons 5-9 region of tumour-derived cell lines was identical to that of diploid Chinese hamster CHL fibroblasts. Sequencing of the amplified fragments showed 100% homology between sequences, which demonstrated the absence of p53 mutations in the exons 5-9 cDNA region expected to have the highest mutability. Nevertheless, the antibody DO-7 recognized the presence of a stabilized p53 protein only in tumour-derived cell lines, which indicated that p53 expression correlated with transformed status.

Amino Acid Sequence↗
PubMed1998

[Minimally invasive treatment of female urinary incontinence due to sphincter incompetence].

Urinary incontinence is one of the most frequent diseases in female urology. There are hundreds of therapeutic opportunities without sure outcomes, because of lack of the etiologic cause. Transurethral injection has good results in around of the 60% of the cases with minimal invasivity, good patients compliance, ripetitivity of the method. From 1993 to 1997 we treated 44 ladies with urinary incontinence due to low pressure of closure of the sphincter: 13 patients (29.55%) disease free, 17 (38.64%) meliorate.

Adult↗
PubMed1998

[Epidermoid cyst of the testicle: presentation of a case].

OBJECTIVE: To describe a case of epidermoid cyst of the testis, a rare lesion that warrants surgical exploration to confirm the diagnosis since its echo patterns are characteristic but not pathognomonic. METHODS/RESULTS: 10 years earlier the patient had noticed an asymptomatic swelling of the right testis which did not cause infertility since he had two children over the last 6 years. Tumor markers AFP, BHCG and LDH fell within the normal ranges. Ultrasound evaluation with a high resolution 7.5 Mhz transducer revealed a 4 x 3.5 x 3.2 cm testicular mass surrounded by atrophic parenchyma. The patient underwent radical inguinal orchidectomy. CONCLUSIONS: Epidermoid cyst is the benign variety of testicular teratoma. Two different forms exist: simple and mixed. Malignant components are present in the latter form. If the simple form is identified before substitution of the testicular parenchyma occurs, testis sparing surgery is justified; otherwise radical orchidectomy with inguinal exploration is indicated.

Adult↗
PubMed1992

Glucocorticoid stabilization of actin filaments: a possible mechanism for inhibition of corticotropin release.

The mechanism by which glucocorticoids induce various cellular responses in different tissues is only partially understood. Here we demonstrate that glucocorticoids stabilize the actin cytoskeleton of several cell types, as revealed by increased resistance of actin filaments to the disrupting effect of cytochalasin and by visible thickening of actin filament bundles. These effects require several hours to develop, require protein synthesis, and are accompanied by increased expression of the actin-binding protein caldesmon. These data may help to explain why glucocorticoids inhibit corticotropin release from pituitary cells, if interpreted in terms of the current idea that an actin filament "barrier" modulates exocytotic secretion in various cell types. In support of this idea, we find that in "model" corticotrophs (AtT-20 cells), glucocorticoids stabilize actin filaments and inhibit corticotropin release with similar potencies. Furthermore, we show here that glucocorticoid inhibition is overcome by exposing AtT-20 cells to concentrations of cytochalasin B or D that disrupt their stabilized actin filaments. On the other hand, our freeze-etch electron microscopy of AtT-20 cells has shown that actin filaments do not, in fact, create a dense submembranous barrier that might prevent corticotropin secretory droplets from discharging; instead, they form open networks near the membrane that appear to hold secretory droplets in their interstices. We propose that the delicate physical crosslinks maintaining this actin-mediated membrane "docking" of secretory droplets may need to disconnect in order to permit corticotropin discharge and that these crosslinks may be stabilized along with the actin filaments in dexamethasone-treated cells.

Actin Cytoskeleton↗
PubMed1990

[Role of ultrasonic diagnosis in patients with clinically suspected acute intestinal invagination].

Acute intestinal intussusception is one of the commonest causes of abdominal emergency in infants. It strikes mainly infants 3 to 30 months old. Ileo-colic intussusception is the commonest form (75-95%), whereas ileo-ileo-colic, colono-colic and ileo-ileal intussusceptions are rather uncommon. Intussusception is primitive in 95% of cases and secondary in the extant 5%. Over the last 3 years we examined 25 infants with clinical suspicion of acute intestinal intussusception by means of plain abdominal radiographs and US. In 11 cases US diagnosed acute intestinal intussusception. US signs useful for diagnosis were: intussusception "pudding" on both transverse and longitudinal scans, and communicating intussusception "pudding" and bowel. US allowed intestinal intussusception to be diagnosed in 11 cases and ruled out in 14, with 100% reliability. In agreement with literature data, our results confirm US as the method of choice--versus conventional radiology--in the diagnosis of acute intestinal intussusception and stress the value of US studies in helping avoid surgery.

Acute Disease↗
PubMed1989

[The role of echography in the diagnosis of neonatal clavicular fractures].

The authors' aim was to investigate the utility of US in the diagnosis of clavicular fractures in neonates. The technique, which is quite simple, consists in obtaining longitudinal scans of the bone by directing the probe along its axis. Ten cases of clavicular fracture were demonstrated in 11 neonates. Some patients were reexamined after 15 days to investigate fracture healing. After US examination, plain X-rays were always performed and the results compared: perfect correspondence was demonstrated between US and X-ray findings. Since clavicular fractures have a very good prognosis, this affection only needs documenting, for which purpose US can fully replace conventional X-rays, being quite simple to perform and avoiding the use of ionizing radiations, though yielding the same diagnostic results.

Clavicle↗
PubMed1985

[Lung cancer of scars. Old and new problems].

The authors report fifteen cases of scar cancers of the lung and one case of tuberculoma. After reviewing both the type of scars and the lung districts involved by the lesions, they conclude that any although tiny scar must be regarded as suspect when a minimal change is noted.

Adenocarcinoma↗
PubMedDate not supplied

Urinary kallikrein activity is not altered in human essential hypertension.

Urinary kallikrein excretion was evaluated in 85 normal subjects and in 149 uncomplicated and recently diagnosed essential hypertensive patients. Moreover, the possible interrelationships between urinary kallikrein excretion and age, sex, electrolyte excretion, and plasma renin activity were examined. In patients with essential hypertension, urinary kallikrein excretion was similar to that of normal subjects. In these patients the enzyme was weakly and positively related to urinary potassium and plasma renin activity; no correlation was found with blood pressure, urinary sodium, age, or sex. In normal subjects and in patients with essential hypertension, the variables studied account for only 25% and 17%, respectively, of the variability of urinary kallikrein excretion. We conclude that the relatively short duration of hypertension in our patients may explain the unaltered values of urinary kallikrein excretion with respect to controls.

Adult↗
PubMedDate not supplied

Normal-phase liquid chromatographic determination of menadione in animal feeds.

A simple method is presented for determination of menadione in vitamin premixes and feedstuffs by normal-phase liquid chromatography (LC). Vitamin K3 is extracted and converted to free menadione, which can be determined directly by LC analysis. Peak area or height is measured at 251 nm, and menadione is quantitated by comparison with the working standard. Menadione can be estimated with a detection limit of 2.5 ppm. Recoveries for premixes ranged from 97.3 to 98.3% and for feedstuffs from 93.7 to 96.8%. The method allows the assay of all commercial K3 compounds in pure or stabilized form and is applicable to a wide variety of feeds and premixes.

Animal Feed↗