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E Marchi

Publications and source records attributed to E Marchi.

At least 73 records · Page 4Linked to original sources
PubMed1984

Antimycobacterial activity of rifaximin (L/105) in experimental tuberculosis in the guinea pig.

The antimycobacterial activity of rifaximin was studied in the guinea pig, after oral administration. The experiment confirmed the scanty absorption of rifaximin in the gastrointestinal tract, as the two dosages used (60 and 30 mg/kg) did not modify the tubercular illness after four months of therapy. Furthermore, sensitivity to rifaximin of the callenging Mycobacterium tuberculosis isolated at the end of the study from the spleen, lung, liver and lymph nodes of the guinea pigs that received rifaximin did not change.

Animals↗
PubMed1984

Kinetics of penetration and clearance of mezlocillin in the bronchopulmonary tract.

Mezlocillin is an expanded spectrum semisynthetic penicillin for parenteral administration, with a good activity against a wide range of pathogenic bacteria including most anaerobes. The pharmacokinetic parameters of mezlocillin were determined in serum and sputum at the first and the seventh day of treatment with 1 g/im/12 h in patients suffering from bronchopulmonary infections. In a second group of volunteer patients who had to undergo surgery for lung cancer, mezlocillin levels in pulmonary tissue and the corresponding serum levels were determined at different times after drug administration. The data obtained made it possible to obtain information on the penetration and clearance of this drug in the bronchopulmonary tract in comparison with that of the serum. The pharmacokinetic behaviour of mezlocillin ensures an efficient antibacterial action in the respiratory tract.

Bronchi↗
PubMed1984

Rifaximin (L/105), a new topical intestinal antibiotic: pharmacokinetic study after single oral administration of 3H-rifaximin to rats.

Tritiated rifaximin was administered in a single oral dose of 10 mg/kg (specific activity 8.998 microCi/mg) and 100 mg/kg (specific activity 0.786 microCi/mg) to rats. After treatment, at fixed times, the animals were sacrificed and the radioactivity in plasma, urine, feces, and in the principal organs and tissues was measured. The radioactivity present in the feces of the two groups of rats was more than 95% of the administered dose, while the amounts found in the urine ranged between 1.15% and 1.5% of the dose. In the plasma and tissues the radioactivity levels were very low. This evidence confirmed the scanty gastroenteric absorption of L/105. Furthermore, as the radioactivity levels maintained almost the same value during the trial, there was the possibility that the amounts found were in part due to isotopic exchange between tritium of 3H-L/105 and hydrogen of water.

Administration, Oral↗
PubMed1983

Denaturation of some general DNA sequences.

In this paper we study a DNA model, which is built by considering all probable sequences, where the possibilities of having the base pairs (A-T) or (C-G) in the jth place of the strand helix are considered. This is assumed in order to derive the partition function. From here the denaturation curve is obtained. Finally, some considerations about the correlation coefficients are presented.

Animals↗
PubMed1983

Evaluation of domifen bromide in the treatment of acute infectious oral diseases.

By means of a double blind, placebo controlled trial, we have studied 29 patients (14 M and 15 F) affected by different acute infectious oral diseases. Our results suggest that domifen bromide may be useful in treating infectious oral diseases in combination with antibiotics, and in relieving pain and inflammation.

Acute Disease↗
PubMed1981

Synthesis and antibacterial activity of some ester, amides, and hydrazides of 3-carboxyrifamycin S. Relationship between structure and activity of ansamycins.

Esters, amides, and hydrazides of 3-carboxyrifamycin S were synthesized by oxidizing the cyanohydrin of 3-formylrifamycin SV to 3-(cyanocarbonyl)rifamycin S, followed by treatment with alcohols, amines and hydrazines. The in vitro microbiological activity of the derivatives was quite low, especially toward Gram-negative bacteria. This poor activity was not shown to be due to the inadequate inhibiting action on the bacterial DNA-dependent RNA polymerase but to the poor penetration of the compounds through the bacterial cell wall. The microbiological activity was correlated to the chemical properties of the substituent on C3.

Anti-Bacterial Agents↗
PubMed1977

Synthesis and antibacterial activity of some derivatives of tolypomycinone. Relationship between structure and activity in ansamycins.

3-Aminotolypomycinoes and 3,16-diamino-16,17-dihydrotolypomycinones are formed by the addition of primary and secondary amines to tolypomycinone, obtained by mild hydrolysis of the antibiotic tolypomycin Y.3-Amino-16,17-dihydrotolypomycinones are formed by the addition of primary and secondary amines to 16,17-dihydrotolypomycinone. In vitro microbiological tests showed high antibacterial activity in compounds obtained by the addition of primary amines, which must be unbranched in the alpha position to the nitrogen atom to position 3 of the naphthoquinone ring. The relationship between structure and activity is described, and evidence is presented that hydrogen bonding between the amino NH bonded to C3 and the amide CO of tolypomycinone is very important for biological activity.

Escherichia coli↗
PubMed1967

E-points of games.

Explore the source record for details and available documents.

Journal Article↗
PubMedDate not supplied

Low concentration silver nitrate pleurodesis in rabbits: optimal concentration for rapid and complete sclerosing effect.

Pleurodesis is a useful therapeutic tool when local treatment of a recurrent malignant pleural effusion or pneumothorax is needed. We have previously demonstrated that the intrapleural injection of 0.5% silver nitrate (SN) produces a significant pleurodesis, while 0.25% SN has no sclerosing effect in a rabbit model. The objective of this study was to determine the minimum concentration of SN needed to induce pleurodesis in our experimental model. One hundred twenty male New Zealand white rabbits received 0.3, 0.4, or 0.5% SN (40 animals per group) in a total volume of 2 mL instilled intrapleurally. These animals were sacrificed 3, 7, 14 or 28 days after the intrapleural injection (n = 10 animals per group), and the pleural spaces were then assessed grossly for evidence of pleurodesis and microscopically for evidence of fibrosis and inflammation. By 28 days, all concentrations of SN had produced a pleurodesis. There was evidence of a gross pleurodesis 7 days post-injection in animals that received 0.5% SN (score of 2.8 +/- 0.2 on a scale of 0-4). After 14 days, significant pleural adhesions were evident in the groups that received 0.4 or 0.5% SN. We conclude that SN concentrations as low as 0.3% can effectively produce a pleurodesis within 28 days of intrapleural injection. However, the precocious pleurodesis development observed 7 days after the intrapleural injection of 0.5% SN suggests that this concentration may be optimal when a fast result is necessary.

Animals↗
PubMedDate not supplied

Effectiveness of silver nitrate compared to talc slurry as pleural sclerosing agent in rabbits. Influence of concomitant intrapleural lidocaine.

UNLABELLED: The ideal agent for producing pleurodesis has not been identified. Talc, the most commonly used, poses several problems. Another possibility is silver nitrate, which was widely used in the past. PURPOSE: To determine the influence of the intrapleural instillation of lidocaine in producing a pleurodesis with silver nitrate, to define the effect of lidocaine in the maturation of the collagen fibers, and to confirm that the pleurodesis after silver nitrate is stronger than after talc. METHODS: We studied three groups of 8 rabbits. Two groups received 0.5% silver nitrate; in one we had previously injected 0.5 ml of 2% lidocaine. The third group received 400 mg/kg talc (2 ml). The animals were sacrificed 28 days after the injection, and the pleural spaces were assessed grossly for evidence of pleurodesis and microscopically for evidence of inflammation and fibrosis. The total amount of pleural collagen and the distribution of thick and thin collagen fibers were quantified. Collagen was identified using picrosirius red stain. RESULTS: In the two groups that received silver nitrate (without lidocaine: 3.5 + 03 and with lidocaine: 3.2 + 0.3), the macroscopic pleurodesis (scale 0 - 4) was significantly (p = 0.001) better than that resulting from talc (1.6 + 0.2). The mean degree of pleural fibrosis induced by silver nitrate (3.5 + 0.2) was significantly (p = 0.004) higher than that induced by talc (1.9 + 0.1). The previous instillation of lidocaine resulted in a tendency for decreased amounts of fibrosis (3.1 + 0.4). The mean amount (10(3)mm2) of pleural collagen was significantly (p = 0.009) greater in the rabbits that received silver nitrate (116.9 + 22.7) than in those that received talc (10.7 + 3.4). The injection of lidocaine slightly reduced the collagen (80.1 + 30.3). The distribution of collagen fibers did not differ among the groups. CONCLUSION: This rabbit model clearly confirms that intrapleural silver nitrate is more effective than talc for producing pleurodesis. The previous intrapleural instillation of lidocaine results in a decreasing trend in the amount of collagen, but does not change the effectiveness of the pleural fusion or modify the process of collagen maturation.

Anesthetics, Local↗