Biomedical subjects
Publications and source records attributed to G Costa.
The authors report two cases of papillary-cystic tumor of the pancreas in two young women. Making a review of literature, they emphasize the rarity of this neoplasm and analyze the possible histopathologic origin, the difficult diagnosis before surgery, surgical therapy and the good prognosis of this pancreatic "curable" tumor.
Patch clamp analysis of membranes reconstituted with a fraction isolated from detergent-solubilized mitochondrial membranes by affinity chromatography on immobilized quinine earlier indicated the presence of two classes of ion channels, of about 40- and 140-pS conductance in medium including 150 mM KCl. Now a 57-kDa constituent of the quinine-affinity column eluate has been identified as the 40-pS channel. Protein fractions derived from the quinine-affinity column eluate by preparative isoelectric focusing with a Rotofor cell have been reconstituted into phospholipid vesicle membranes by detergent dialysis, and vesicles have been enlarged for patch clamping by dehydration and rehydration. Voltage clamp analysis has been carried out on excised patches bathed symmetrically in buffered medium containing 150 mM KCl and 100 microM CaCl2. Patches of membrane incorporating the 57-kDa protein exhibit 40-pS conductance transitions. The magnitude of conductance transitions is similar when Na+ replaces K+ in the bathing medium, indicating little selectivity of the 40-pS channel for K+ relative to Na+. Another fraction derived from the quinine-affinity column eluate is found to contain the larger channel, now estimated to have an average conductance of about 130 pS. Patches of control membrane prepared in the same way but without protein exhibit no channel activity.
The genetically epileptic-prone rat (GEPR) is a valuable model for the study of gene-linked abnormalities involved in epilepsy. In comparison with normal Sprague-Dawley controls, we found, in GEPRs, a marked depression in local cerebral glucose utilization, widespread throughout the brain. This depression was accompanied by a significant increase of blood-brain barrier permeability and a reduction in regional blood volume. Finally GEPRs showed lower plasma levels of total triiodothyronine than normal controls. One can speculate that alterations in cerebral metabolism and microvascular regulation and thyroid hormone imbalance may be gene-linked factors involved in seizure susceptibility.
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In order to clarify whether an interaction between endogenous opioids and feeding occurs at birth, we studied Beta-endorphin (beta-EP) and ACTH plasma levels in response to a feed of 10% glucose, or formula, in 120 healthy full-term infants. Neither postprandial beta-EP nor ACTH increases were found at the 24th hour or on the fourth day of life. beta-EP physiology in newborn infants seems to be different from adults.
1. In vitro experiments were designed to characterize postjunctional alpha-adrenoceptor subtypes in ring segments (1 mm length; outer diameter 300-500 microns) from arteries supplying the oviduct of the heifer. 2. Noradrenaline, adrenaline and phenylephrine evoked concentration-dependent contractile responses. The pD2 values were 5.67, 5.89 and 5.93, respectively. Medetomidine clonidine and B-HT 920 (2-amino-6-allyl-5,6,7,8-tetra-hydro-4H-(thiazo)-4,5-d-azepoine ) were ineffective. 3. The alpha-adrenoceptor selective antagonists, prazosin (1 nM-0.1 microM) and rauwolscine (0.1-10 microM) competitively antagonized the response to noradrenaline. The pA2 values were 9.38 and 6.83, respectively. 4. The dissociation constant (KD) for noradrenaline calculated by use of the irreversible antagonist, dibenamine, was 3.95 (2.09-5.81) microM. The occupancy-response relationship was non-linear. Half-maximal response to noradrenaline was obtained with 22% receptor occupancy while maximal response required 100% occupancy. 5. B-HT 920 evoked a biphasic contractile concentration-dependent response in preparations incubated in a physiological solution containing 20 mM K+, 0.1 microM prazosin and 1 microM propranolol. Rauwolscine 0.1 microM significantly (P less than 0.01) blocked the first component of the B-HT 920 concentration-response curve with an apparent pA2 value of 8.52 (7.86-9.18). 6. These results strongly suggest that alpha-adrenoceptors in oviductal arteries are mainly of the alpha 1 subtype, although a possible role for alpha 2-adrenoceptors cannot be excluded.
The effect of the dopaminergic antagonist haloperidol on the permeability of the blood-brain barrier (BBB) to [14C]alpha-aminoisobutyric acid was studied in 10-12- and 28-30-week old rats. Following the intraperitoneal injection of haloperidol (1 mg kg-1), an increase in the permeability of the BBB, with respect to younger animals, was observed within the occipital cortex, striatum, hippocampus and hypothalamus in the older rats. No correlation was found between haloperidol-induced changes and age-related differences in the permeability of the BBB. Such age-associated increase in the vulnerability of the BBB when challenged with haloperidol might be related to a deterioration of the dopaminergic control of cerebrovascular permeability.
Cancer risk for farmers in Denmark and Italy was studied by linking occupational census data with incidence of cancer in Denmark and with cancer mortality in Italy. Farmers in the two countries had a consistent risk reduction for cancer of the lung, bladder, small intestine, colon, rectum, and prostate. No excess of stomach cancer was found among farmers in the two countries, which is in agreement with the most recent data from other surveys. The risk of oesophageal cancer was reduced among the Danish and increased among the Italian male farmers. This can probably be explained by differences in alcohol consumption between the Danish and Italian farmers compared with the general population. The risk of brain cancer was significantly reduced among Italian farmers. There was a significant risk reduction for Hodgkin's disease and no excess for non-Hodgkin's lymphoma in Denmark, whereas in Italy a statistically significant excess risk was found for the first and a slight excess risk for the second of these diseases. The per capita consumption of phenoxy-herbicides between 1950 and 1970 was lower in Italy than in Denmark but treatments were performed mainly by professional applicators in Denmark and by the farmers themselves in Italy. Risk of leukaemia among Italian female farmers was increased. In Denmark, this increase was limited to women who were themselves owners of a farm. Specific occupations in agriculture showing a high risk for cancers of the lymphopoietic system in Denmark mostly entailed contact with animals.
The authors report 2 cases of localized xanthogranulomatous pyelonephritis (XGP) in which computed tomography (CT) permitted to raise a motivated clinical suspicion of inflammatory disease: the surgical exploration documented absence of neoplasm and allowed a conservative therapy implying only the removal of the mass. A literature review confirms that some CT signs in XGP permit differentiation from carcinoma. If they are present, in unifocal cases of disease, the authors suggest a limited surgical approach and a therapeutic strategy as conservative as possible.
We studied HLA-DQB1 haplotypes in 103 unrelated multiple sclerosis (UMS) patients and in 26 related (RMS) patients from 12 families from Sardinia, Italy, where the disease was associated with the HLA-DR4 allele. Using polymerase chain reaction and allele-specific oligonucleotide probes, we found in UMS an increased frequency of the DQB1 *0201 (p = 0.010) and DQB1 *0302 (p = 0.025) alleles, whereas the DQB1 *0301 allele was significantly decreased (p = 0.027). In RMS, only the DQB1 *0302 allele was increased (p = 0.047), and no difference was found in the DQB1 *0301 allele. For DQB haplotypes, an increased frequency of DQB1 *0302/*0502 (p = 0.026) and a decreased frequency of DQB1 *0201/*0601 (p = 0.009) and DQB1 *0502/*0502 (p = 0.025) was found in UMS patients, whereas RMS patients showed an increased frequency of DQB1 *0301/*0302 (p = 0.005). Because DQB1 *0201 and *0302 alleles are increased in Caucasian MS patients, where the disease is related to HLA-DR2 and where a primary association with the HLA-DR2, DQB1 *0602 allele has been reported, we conclude that Caucasian and Sardinian populations share HLA-DQB1 *0201 and *0302 alleles in genetic susceptibility to MS.
We investigated the efficacy of danazol treatment in eight patients with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). Treatment with danazol yielded clinical improvement of urinary control and gait disturbances in 7 out of the 8 patients. The improvement was noted within 15 days of danazol administration. Analysis of factors of relevance to the clinical improvement with danazol showed that the beneficial response was preferentially found in females.
The Turin longitudinal study enables to study the one-year survival of children born to any member of the study population and to relate the still-born and infant mortality to the parents' census characteristics. In this paper 25,108 children, born between 1981 and 1985 of parents residents in Turin at the 1981 population census, were followed up with respect to one-year survival. The numbers of infant deaths have been observed according to parents' education, housing ownership, occupational status and professional position. Only parents' education showed consistent differential in the still-born and infant mortality risks, adjusted for maternal age.
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Indomethacin inhibits prolactin liberating effects by MET-enkefalin-NH2, a synthetic analogue of MET-enkefalin, both in intact and in ovariectomized, estradiol benzoate treated rats. The introduction of PGE1 increases the intensity of this effect. It is therefore possible to suppose that the PGs are involved as intermediaries of the prolactin relasing effect induced by MET-ENH-NH2.
Angiotensin II increases aldosterone production of isolated and superfused bovine adrenal glands. Indomethacin shows a bi-phasic effect on the production of the above-mentioned hormone, inhibitory at low doses (0,2 microgram/ml), stimulatory at high doses (5.0 microgram/ml). Preincubation with this drug impedes the increase of aldosterone production induced by angiotensin II. It is likely that the steroidogenetic effect of angiotnesin II is carried out through the PGs.
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