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Biomedical subjects

S Ferri

Publications and source records attributed to S Ferri.

At least 91 records · Page 5Linked to original sources
PubMed1990

Morphine affects prodynorphin gene expression in some areas of rat brain.

The effect of a chronic morphine treatment on prodynorphin gene expression has been studied. Morphine has been intraperitoneally administered twice daily for seven days into rats. RNAs from hippocampus and striatum have been extracted and analyzed with probes complementary to the prodynorphin mRNA. A marked reduction in mRNA levels was detected in hippocampus, following chronic morphine treatment; in striatum results showed either a slight decrease or no substantial changes in mRNA levels. These results indicate that the chronic morphine is able to induce modifications in the homeostasis of the endogenous opioid gene expression, at least in some areas of the rat brain. In addition, our data support the hypothesis that a tolerance to opiates might involve alterations in functions of brain pathways which utilize the opioid peptidergic system.

Animals↗
PubMed1989

Hypothermia elicited by some prodynorphin-derived peptides: opioid and non-opioid actions.

Prodynorphin-derived peptides were tested for their effects on body temperature after intracerebroventricular administration to unrestrained male rats. Dynorphin A (Dyn A) (5 and 10 nmol) and Dynorphin A-(1-32) (Dyn A-(1-32) (2.5 and 5 nmol) lowered body temperature with a maximum approximately 30 min after administration. Dyn B (up to 50 nmol) did not induce hypothermia. Lower doses of all peptides did not alter body temperature. The hypothermic effect was significantly, but not completely prevented by MR1452 (30 nmol), a preferential antagonist of the kappa receptor, administered intracerebroventricularly. Naloxone, a mu receptor antagonist, naltrexone, its long acting analog up to doses of 100 nmol, as well as MR1453, the (+)-enantiomer of kappa antagonist MR1452 with no opioid binding properties, did not prevent the hypothermic effect. Moreover, episodic barrel rolling and bizarre postures elicited by Dyn A and Dyn A-(1-32) were reduced in rats pretreated i.c.v. with MR1452 (30 nmol), but not with naloxone (up to 100 nmol). Interestingly, des-Tyr-Dynorphin A (Dyn A-(2-17)), a fragment with virtually no opioid binding potential, was 4 times less potent that Dyn A in inducing hypothermia. These findings are consistent with the hypothesis that prodynorphin-derived peptides effects are not exclusively opioids in nature.

Animals↗
PubMed1989

Fat intestinal absorption in the catfish--a histochemical study in glycol methacrylate embedded tissue.

The intestinal absorption of lipids was investigated in plastic sections from glycol methacrylate embedded intestine after fat administration. In the catfish, the lipids are absorbed by the enterocytes of the proximal intestinal segment, thus forming fat cytoplasmic inclusions that were demonstrated by Sudan black B staining. The histochemical characterization of lipids by the Nile blue sulphate test revealed the neutral or triglyceride nature of the cytoplasmic droplets, both after the corn oil and oleic acid feeding. There is lipid accumulation in the lamina propria and lymphatic vessels.

Animals↗
PubMed1988

Role of the ventromedial hypothalamus in the regulation of adenohypophyseal immunoreactive dynorphin in the rat.

In this study, we have examined the role of the dorsomedial (DMH), ventromedial (VMH) and arcuate (ARH) nuclei of the hypothalamus in the control of hypothalamic and pituitary immunoreactive (ir) dynorphin (Dyn) A and ir-Dyn B in the rat, by evaluating the effect of discrete, bilateral radiofrequency lesions in these structures. Lesions limited to the VMH reduced the content of ir-Dyn in the anterior pituitary but not in the neurointermediate lobe or in the hypothalamus. Gel chromatographic analysis of anterior pituitary extracts confirmed that ir-Dyn is mainly associated with high molecular weight forms containing Dyn A and Dyn B in their sequence. Anterior pituitary extracts of VMH-lesioned rats displayed a clearly lower proportion of these forms. Destruction of the DMH affected only the hypothalamic content of ir-Dyn; ablation of the ARH did not cause any significant change. Our results suggest that ablation of the VMH may disrupt critical neuronal connections to the median eminence originating in this nucleus or crossing it and participating in control of the adenohypophyseal pool of ir-Dyn.

Animals↗
PubMed1988

Regional distribution of immunoreactive dynorphin A in the human gastrointestinal tract.

Immunoreactive dynorphin A (ir-Dyn A) was detected throughout the human gastrointestinal tract by a validated radioimmunoassay. Moreover, the stability of 125I-Dyn A during extraction procedures was confirmed by high performance liquid chromatography. Levels of ir-Dyn A were higher in the stomach and in the small bowel. In tissue samples separated into the main layers composing the gut wall (muscularis externa, submucosa and mucosa) ir-Dyn A was uniformly distributed. An exception was the colon, where concentrations were higher in the muscular portion. Gel permeation chromatography on samples of mucosa and muscularis externa extracts of ileum and gastric fundus, showed immunoreactive material eluting in several forms of apparently higher molecular weight than Dyn A, while only a minor peak was found to coelute with authentic Dyn A.

Digestive System↗
PubMed1988

Localization of the active principles of the male fern (Dryopteris filix-mas (L.) Schott.) by fluorescence microscopy.

The active principles of the male fern, Dryopteris filix-mas (L.) Schott., consisting of a mixture of phloroglucinol derivatives called "crude filicin", are localized by means of fluorescence microscopy under U.V. 365 nm and monochromatic blue 435-490 nm lights. Crude filicin is autofluorescent, and therefore may be easily localized in the internal glandular hairs of the intercellular spaces of rhizome and leaf bases parenchyma, without pre-treatment of sections. Localization is confirmed both morphologically and chemically, and is possible on a fresh material, as well as on a desiccated one. The test allows also a complete anatomical examination of sections, and may be useful, for its easiness and quickness, in further taxonomic or pharmacognostic studies.

Butyrophenones↗
PubMed1988

Protection by opioids against gastric lesions caused by necrotizing agents.

The synthetic opioid met-enkephalin analog [D-Ala2, MePhe4, Met(0)5ol] enkephalin (DAMME) and the opiate morphine injected intraperitoneally to rats at doses of 0.5-2 and 5-20 mg/kg, respectively, showed a protective effect on gastric damage induced by oral administration of necrotizing agents (0.6 N HCl or 0.2 N NaOH solutions, 1 ml/rat). The protection was prevented by naltrexone (10 mg/kg s.c.), an opioid antagonist with long-lasting activity. Histological sections of mucosal samples from animals pretreated with morphine (10 mg/kg i.p.) and DAMME (1 mg/kg i.p.) showed less alteration of the columnar epithelium, with a normal glandular structure, than untreated rats. A mediation of prostaglandins is suggested, since indomethacin (10 mg/kg s.c.) significantly reduced the protective effects of opioids.

Animals↗
PubMed1988

Environmental and social factors in rheumatoid factor epidemiology.

The effect of social and environmental conditions on the epidemiology of Rheumatoid Factor (RF) in healthy population was studied. For this purpose 2 sample of 828 subject was studied using 5 tests for RF. Our sample included: 419 randomized subjects from a quarter at the outskirts of Bologna (high rate immigration, non homogeneous habits and health background; 409 randomized subjects from one rural small town on the Romagna's hills (no immigration, no change in residence or profession for generations, uniform, habits and health background). These tests included: three on slide with binded human (2) and rabbit (1) IgGs and sheep-cells tests-one on slide (Scat) and the other in tube (W.-Rose by Mizuoka). The most frequent positive test was Scat test, in urban population and one human IgG latex-test in the rural population. No urban subject reacted at the same time to 4 or 5 tests. Associated positive results for 2, 3 or 4 tests are usually observed in rural subjects. These results are the expression of the different and more uniform social and biological background acquired by rural people.

Adult↗
PubMed1988

Evolution of the rheumatoid factor over time.

With purpose to verify the epidemiological value of the Rheumatoid Factor's variations over time, we studied: 421 RA at first hospitalization (from 1976 to 1985; Group A); 348 consecutive RA with follow-up at 0, 6, 12, 24, and 48 months (Group B); 750 subjects, chosen at random from a healthy population, before and after 48 months (Group C). Five agglutination tests were used: three latex tests with human (2) and rabbit (1) IgGs; one red cells test on slide, and one in tube. The results were: uneven variations in positive results in all tests (Group A); the maximum confirmation of the basic profile are provide in short-term follow-up; in subsequent follow-ups, with the exclusion of the case of all the negative tests, the remaining profiles have a decreasing confirmation rate (Group B); the positive frequency is different in all the tests; this trend is sustained at follow-up (4 years later) in spite of the overall increase of positive results (Group C). Serum-positive RA, according to all or many tests, tend to reduce the number of positive results; healthy subjects (with few positive tests) tend to increase the number of positive results over time. RA with all the negative tests have a reasonably constant profile.

Agglutination Tests↗
PubMed1988

Nonsteroidal anti-inflammatory agents. Part 17: Stereomeric o-, m-tolyl- and anisyl-biphenylyl-hydroxypropionic acids.

As a part of wider research project on chiral anti-inflammatory arylacanoic acids, the 3-(o- and m-)-(methyl and methoxy)-phenyl-2-biphenylyl-3-hydroxypropionic acids 3a-d were synthesized and resolved in their optically active erythro and threo stereomers, which were submitted to the carrageenan induced rat paw edema test. With respect to the p-isomers, only the threo p-methoxy substitution enhances the anti-inflammatory activity. Some conclusions on structure-activity relationship are discussed.

Animals↗