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Biomedical subjects

S Selleri

Publications and source records attributed to S Selleri.

At least 37 records · Page 2Linked to original sources
PubMed1993

Synthesis and study of the anti-inflammatory properties of some pyrazolo[1,5-a]pyrimidine derivatives.

A series of pyrazolo[1,5-a]pyrimidin-7-ones (1c-17c) were synthesized to evaluate in vivo and in vitro effects induced by structural modifications at the 2 position of 4,7-dihydro-4-ethyl-2-phenylpyrazolo[1,5-a]pyrimidin-7-one (FPP028). This substance, which has been previously studied, is a weak inhibitor of prostaglandin biosynthesis and a nonacid analgesic and anti-inflammatory agent devoid of ulcerogenic properties. To gain more insight into the mechanism of action of this class of compounds, several in vivo tests were carried out, such as carrageenan-induced rat paw edema and pleurisy. In vitro tests include some studies of leukocyte functions, such as superoxide production and myeloperoxidase release. In vitro effects on arachidonic acid-, adenosine 5'-diphosphate-, and platelet-activating factor-induced platelet aggregation were also studied. Different anti-inflammatory activities were observed, depending on the nature of substituents at the 2 position; these differences are probably linked to the capacity of these compounds to inhibit leukotrienes and/or prostaglandin biosynthesis with different selectivity. 4,7-Dihydro-4-ethyl-2(2-thienyl)pyrazolo[1,5-a]pyrimidin-7-one (7c) proved to be the most interesting compound of the novel synthesized series, showing powerful pharmacological activity in vivo as well as in vitro, together with very weak acute toxicity.

Animals↗
PubMed1993

Redo pouches: salvaging of failed ileal pouch-anal anastomoses.

From October 1, 1984 to December 31, 1991 at the Clinica Chirurgica II of the University of Bologna, 140 patients submitted to ileal pouch-anal anastomosis for ulcerative colitis (UC) and familial adenomatous polyposis (FAP). Nineteen patients (13.5 percent) developed septic complications. Of these, 11 patients (7.8 percent) had pelvic sepsis. Eight patients required further surgical intervention. Five patients underwent the redo pouch procedure. Another redo pouch was performed in a patient who had previously, in another hospital, had an ileal pouch-anal anastomosis placed and then removed because of ischemic necrosis of the reservoir. No deaths are reported in the reoperated patients. Currently, five of the six patients who underwent the redo pouch procedure have a well-functioning ileoanal anastomosis. The redo pouch procedure should always be attempted prior to the establishment of pelvic fibrosis.

Adult↗
PubMed1993

Colo-anal anastomosis with colonic reservoir for cavernous hemangioma of the rectum.

The authors report on the clinical history of, and the therapeutic choices for, cavernous hemangioma of the rectum diagnosed in a 27-year-old male admitted for repeated episodes of rectal bleeding. The hemangioma extended to the dentate line and consequently the surgical challenge was to carry out a sphincter-saving procedure. The low resting pressure of the sphincter did not rule out the use of the colo-anal anastomosis procedure, but did require the construction of a pre-anastomotic colonic reservoir. The diagnostic problems and the therapeutic choices related to the salvaging of the sphincter are discussed.

Adult↗
PubMed1993

[Comparison of magnetic resonance (0,5 T), computed tomography, and endorectal ultrasonography in the preoperative staging of neoplasms of the rectum-sigma. Correlation with surgical and anatomopathologic findings].

Eighteen cases of rectal carcinoma were staged preoperatively with transrectal endosonography (EUS), CT and MRI (0.5 T). The results were compared with surgical specimens and histology to evaluate the accuracy of the imaging modalities in staging rectal carcinomas which had been quantified according to Astler-Coller's classification. All methods identified the lesion (100% sensitivity). EUS and MRI correctly staged 8 cases (44%) and CT 9 cases (50%). CT and MRI mistakes were relative to overstaging, whereas EUS understaged 4 cases (22%) and overstaged 6 cases (33%). In local tumor staging ("T" variable), CT and MRI understaged no lesions, thus exhibiting 100% sensitivity, which was higher than EUS sensitivity (92%). Conversely, CT and MRI more frequently overstaged the lesions, thus demonstrating lower sensitivity than EUS (55% and 50%, respectively, versus 76% for EUS). As for the "N" variable, EUS identified node metastases in one case only (25%) and misdiagnosed as positive 4 cases of negative node involvement. All the C-stage lesions were correctly diagnosed by CT and MRI (whose findings were in agreement) which also overstaged as C three cases with hyperplastic node enlargement. The diagnostic accuracy of EUS, which was highest for the A and B1 stages, progressively decreased for bigger lesions, clearly understaging node involvement. On the contrary, CT and MRI accuracy rates were lower in small tumors involving the rectal wall only, whereas they always identified tumor spread beyond the bowel wall into perirectal fat, and node metastases. Therefore, to conclude, EUS can be used first: in case of extraluminal tumor spread, CT is the method of choice, more accurate than MRI in identifying node involvement and equally effective in evaluating perirectal fat infiltration and pelvic structures involvement. Whenever the pelvic floor is involved, MRI is the best imaging method, thanks to its multiplanar capabilities, for better detailing of musculoskeletal involvement.

Aged↗
PubMed1993

Synthesis of 7-(2-dimethylaminovinyl) derivatives of pyrazolo[1,5-a] pyrimidines, as precursors of new tricyclic series. Binding studies of BDZ receptor.

A series of 7-dimethylaminovinylpyrazolo[1,5-a]pyrimidines bearing an acetyl or an ethoxycarbonyl group at the 6-position turned out to be useful intermediates for the synthesis of pyrazolo[1,5-a]pyrido[3,4-e]pyrimidines and 8H-pyrazolo[5',1':2,3]pyrimido[5,4-d][1,2]diazepines. These tricyclic derivatives were studied for their affinity for the central benzodiazepine receptor, and meaningful suggestions about the structure-affinity relationship were obtained. Some of the above intermediates were also reacted with S-methylthiourea, to give a mixture of pyrazolo[5',1':1,2]pyrimido[5,6-e][1,3]diazocines and pyrazolo[1,5-a]quinazolines.

Binding, Competitive↗
PubMed1989

The motor response to ethylenediamine of the rat isolated duodenum: involvement of GABAergic transmission?

We have studied the motor response to ethylenediamine (EDA), a well known releaser of endogenous GABA, on the longitudinal muscle of the rat isolated proximal duodenum in presence of atropine (3 microM) and guanethidine (3 microM). EDA produced a concentration-(0.03-3 microM)-dependent relaxation which was potentiated when the preparations were exposed to GABA during the equilibration period. The GABA-induced potentiation of the response to EDA was prevented by nipecotic acid, an inhibitor of GABA uptake. The response to EDA was partially inhibited by 3-mercaptopropionic acid, a known inhibitor of GABA release. However, contrary to the relaxant response produced by exogenous GABA, the EDA-induced relaxation was picrotoxin-(0.1 microM)-resistant. In preparations pre-exposed to GABA, the response to EDA was partially tetrodotoxin-(1 microM)-sensitive. By contrast, in preparations not exposed to GABA, the EDA-induced relaxation was totally tetrodotoxin resistant. The response to EDA was abolished or largely inhibited in preparations excised from rats in which the proximal duodenum was chemically denervated by exposure (2 weeks before), to benzalkonium chloride (BZK). Likewise, the indirect relaxations produced by electrical field simulation. DMPP, capsaicin or GABA were abolished by BZK pretreatment while noradrenaline was still effective. These findings indicate that the relaxant response to EDA is neurogenic in origin, while being largely tetrodotoxin-resistant. A GABAergic mechanism could be involved but also other inhibitory transmitter(s) should be taken into account. EDA appears a useful tool to study the inhibitory non-adrenergic non-cholinergic innervation of the rat proximal duodenum.

3-Mercaptopropionic Acid↗
PubMed1989

Glucose electrochemical probe with extended linearity for whole blood.

A glucose probe based on a suitable modification of the silanization process of commercially available polycarbonate membrane was assembled and evaluated. The silanization procedure was carried out in gaseous phase in an anhydrous atmosphere, with dimethyldichlorosilane in a closed vessel. This new procedure seems to be highly reproducible and has the distinct advantage of fast response time and extended linearity up to 0.1 mol l-1 of glucose. Application to serum samples shows the possibility of application in clinical chemistry.

Biocompatible Materials↗
PubMed1988

The effect of omega conotoxin GVIA, a peptide modulator of the N-type voltage sensitive calcium channels, on motor responses produced by activation of efferent and sensory nerves in mammalian smooth muscle.

1. The effect of omega-conotoxin (CTX) GVIA, a peptide which blocks neuronal calcium channels, were investigated on nerve-mediated motor responses in a variety of isolated smooth muscle preparations from rats and guinea-pigs. 2. In the rat or guinea-pig isolated vas deferens CTX (1 nM-1 microM) produced a concentration and time-related inhibition of the response to field stimulation, while the responses to KCl, noradrenaline or adenosine triphosphate were unaffected. In the presence of CTX a series of tetrodotoxin-resistant contractions could be elicited by field stimulation by increasing pulse width and/or voltage. 3. In the rat or guinea-pig isolated urinary bladder, CTX produced a concentration and time-dependent inhibition of twitch responses to field stimulation without affecting the response to exogenous acetylcholine. In the rat bladder the maximal effect did not exceed 25% inhibition while a much larger fraction of the response (about 70%) was inhibited in the guinea-pig bladder. The CTX-resistant response was abolished, in both tissues, by tetrodotoxin. 4. The effects of CTX in the rat bladder were also studied with a whole range of frequencies of field stimulation (0.1-50 Hz). Maximal inhibition was observed toward contractions elicited at frequencies of 2-5 Hz. At low frequencies the inhibitory effects of CTX and atropine were almost additive while at high frequencies of stimulation a large component of the atropine-sensitive response was CTX-resistant. 5. In the rat isolated proximal duodenum, field stimulation in the presence of atropine and guanethidine produced a primary relaxation followed by a rebound contraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Correlation between plasma or blood transfusion and survival after curative surgery for colorectal cancer.

Out of 473 patients operated radically for colon or rectal cancer different survival curves have been calculated according to whether they had received or not blood or plasma transfusions during their hospital stay. The non-transfused patients have a better 5-year survival rate and the difference is statistically significant both including and not including Duke's C stage cases. Anemia on hospital admission, on the contrary, does not seem to influence patients survival. Immune depression after blood or plasma transfusion is a very well known phenomenon in transplant surgery and actually depends on the infusion of leucocytes. Is not yet clearly demonstrated that in cancer surgery immune depression may lead to a poorer survival of transfused patients but several papers, including ours, suggest that this effect is very likely. At present in cancer patients it is preferable to limit transfusions to the minimum. If they are absolutely necessary leucocyte poor or, better still, leucocyte free preparations should be administered.

Blood Transfusion↗
PubMedDate not supplied

Aorto-enteric fistulae: spontaneous and after aorto-iliac operations.

Ten case of arterio-enteric fistula are presented, 3 spontaneous and 7 following surgery on the aorta. In the majority of cases "herald bleeding" allows enough time to study the patient. Spontaneous fistulae are very rare and their diagnosis can be very difficult if the aneurysm is not palpable. In any case of gastrointestinal haemorrhage in a patient who has undergone an aortic operation an A-E fistula will be suspect. The only useful diagnostic procedure is gastroduodenoscopy which usually does not show any organic cause for the bleeding. Arteriography seems only a dangerous waste of time: emergency explorative laparotomy, if a fistula is suspected, is surely harmless and preferable. The only sure surgical technique consists in removal of the prosthesis followed by an extra-anatomic by-pass.

Aged↗