PubMed Health⌕ Search

Biomedical subjects

G Baggio

Publications and source records attributed to G Baggio.

121 records · Page 7Linked to original sources

In vitro activity of sulphimidazole alone and in association with trimethoprim against enteric pathogens.

Sulphimidazole is a new sulphonamide belonging to the class of intestinal sulphonamides and characterized by the fact that it is active even in vitro. It has the heterocyclic ring of 5-nitroimidazoles on amidic nitrogen. Its antibacterial activity is similar to that of the classical sulphonamides but differs in that it also combats certain anaerobic bacteria such as Clostridium botulinum. This effect is completely absent in the case of sulphadiazine and sulphamethoxazole. Also, since p-amino-benzene-sulphonamide is present in the molecule, the drug acts in synergism with trimethoprim against certain aerobic or facultative strains of enteric pathogens.

Bacteria↗

Gene/longevity association studies at four autosomal loci (REN, THO, PARP, SOD2).

The possibility that four loci (REN, THO, PARP, SOD2) are associated with longevity was explored by comparing the genotypic pools of subjects older than 100 years with those of younger subjects matched for sex and geographic area (northern and southern Italy). The markers (all located within the respective gene) were HUMREN4; HUMTHO1; HUMPARP (gt)845nt; SOD2(C/T)401nt. In order to reduce the number of genotypes, multiallelic polymorphisms were recoded as diallelic according to allele size and frequency patterns (small: S, and large: L, alleles). A significant loss of LL homozygous genotypes was found at the THO locus in male but not in female centenarians with respect to matched controls. On the other hand no significant difference was found between case/control genotypic frequencies at REN, PARP, SOD2 loci. The latter loci therefore do not affect inter-individual variability in life expectancy (at least in terms of qualitative variants associated with the tested markers). However, the data is consistent with an association between the THO locus and longevity.

Adolescent↗

In vitro activity of trimethoprim in association with sulfimidazole against aerobic gram-negative and gram-positive microorganisms and Clostridia.

The in vitro activity of a chemotherapeutic agent, sulfimidazole (SIZ), obtained by combining two molecules belonging to groups of extremely different antibacterial drugs, p-aminobenzene sulfonamide and a derivative with a 5-nitroimidazole ring, was studied. In association with trimethoprim, SIZ induces an intense synergistic antibacterial effect on gram-negative and gram-positive aerobic microorganisms and Clostridia. The results show that, in SIZ, the activity of each starting molecule remains unchanged providing that its structure-action relationship is kept intact.

Anti-Bacterial Agents↗

[The Kern paradigm: professional independence and information demands of the scientific community].

Legislative decrees 277/91 and 626/94 defined in detail role and duties of the occupational physician. There is no normative regulation about ethical principles for occupational professionals although some international organizations, such as the International Commission on Occupational Health (ICOH), are making proposals in this field. In the last decades, these principles have been assuming an increasing importance because of occupational medicine operators' major responsibility and the need of a multidisciplinary approach in work related risk prevention. The aim of this contribution is to present a case about professional independence and commercial secret that involved an occupational physician (David G. Kern), Brown University (that employees him) Memorial Hospital and a textile firm that consulted dr. Kern to investigate a pulmonary disease that affected some employees. The fact has been described by e-mail of OEM (Occupational Environmental Medicine) list. This event underlines the distance between the professional reality and ethical principles formulated in the ICOH code; these principles must be the base for a correct professional activity aiming only at promoting workers' health.

Ethics, Medical↗

The effect of nizatidine on neuromuscular transmission.

The effect of the H2-receptor antagonist, nizatidine, on neuromuscular transmission was investigated using sciatic nerve-gastrocnemius muscle preparations of rat in vivo. Nizatidine, administered by i.v. injection, potentiates the neuromuscular blockade induced by d-tubocurarine, pancuronium and the aminoglycoside antibiotic, kanamycin. Moreover, the drug alone is capable of producing a blockade on preparations stimulated at high frequency. The neuromuscular blockade induced by nizatidine is reversed by 4-aminopyridine but not by dimaprit.

4-Aminopyridine↗

The bactericidal effect on Pseudomonas strains of adriamycin associated with quinolones.

The in vitro antibacterial activity of quinolone compounds was assessed on strains of Pseudomonas aeruginosa isolated from clinical infections. The bactericidal effect of quinolones was high and their respective antibacterial properties with adriamycin remained unimpaired on strains both sensitive and resistant to betalactam and aminoglycoside antibiotics. The cytotoxic effect of the combination of adriamycin and quinolones was determined in cultured P388 leukemia cells: no interference with the cytotoxic activity of adriamycin was observed.

Ciprofloxacin↗

Bactericidal and cytotoxic effect of combination of norfloxacin and 5-fluorouracil.

Using the agar dilution technique, we examined the in vitro antibacterial activity of 5-fluorouracil and norfloxacin alone and in association against several bacterial strains. When administered in association, the two drugs did not antagonize each other in tests carried out on strains both sensitive and resistant to penicillins, cephalosporins, aminoglycosides, tetracyclines; furthermore their respective antibacterial properties remained largely unimpaired. The cytotoxic activity and the antitumoral effect of a combination of 5-fluorouracil and norfloxacin was determined in cultured tumor cells, and in mice bearing Ehrlich ascites carcinoma. No significant interference with the cytotoxic activity and antitumoral activity of 5-fluorouracil was observed.

Animals↗

The effects of roxatidine on neuromuscular transmission.

We have investigated the effects of the H2 receptor antagonist roxatidine on the neuromuscular transmission by using the sciatic nerve-gastrocnemius muscle preparation of the rat in vivo. Roxatidine, administered by i.v. injection, potentiates the neuromuscular blockade induced by d-tubocurarine, pancuronium and aminoglycoside antibiotic, kanamycin. Moreover, the drug alone is capable of producing a blockade on the preparation stimulated at high frequency. The neuromuscular blockade induced by roxatidine is partially reversed by 4-aminopyridine but not by dimaprit.

4-Aminopyridine↗

Glycyrrhizin and 18 beta-glycyrrhetinic acid: a comparative study of the pharmacological effects induced in the rat after prolonged oral treatment.

Recent clinical and toxicological studies have investigated the mineralcorticoid-like and hypertensive effects of liquorice, and we therefore set out to identify the active component responsible for these effects. We conducted a 30-day comparative analysis of glycyrrhizin and 18 beta-glycyrrhetinic acid and found that the latter causes significant variations both in systolic blood pressure and in the excretion in the urine of Ca++. The effects were fully reversible on suspension of treatment.

Administration, Oral↗

Influence of glycyrrhizin on the evolution and respiration of Ehrlich ascites tumour cells.

It has been demonstrated that 18 alpha-glycyrrhetinic acid, 18 beta-glycyrrhetinic acid and glycyrrhizin effectively inhibit the inception and growth of skin tumours. Moreover, glycyrrhizin and its aglycone act on the growth and differentiation of mouse melanoma cells in culture. In this study we investigated the effect of glycyrrhizin, 18 alpha- and 18 beta-glycyrrhetinic acids on the evolution of Ehrlich ascites tumour in mice. A prolonged glycyrrhizin treatment proved to be effective in modifying the animals' survival pattern.

Animals↗

Influence of antimalarials chloroquine, quinine, primaquine and mepacrine on the evolution of Ehrlich ascites tumour.

Substances like imidazoles, benzimidazoles and also quinolines, whose chemical structure includes a heterocyclic nitrogen, are known to interfere with the microsomal oxidation and, in some cases, with the metabolism of drugs. Since chloroquine and primaquine exert this effect in vivo and in vitro, we studied the influence of other antimalarials (quinine and mepacrine) in mice with induced Ehrlich ascites tumour (EAT) to find out whether variations in oxygen consumption affected the course of the disease. In vitro data, obtained by a polarographic technique, indicate that primaquine and, in particular, mepacrine increase EAT-cell oxygen consumption, while in vivo data, obtained in mice injected with an inoculum of about 1 x 10(6) tumour cells per mouse, show that both drugs, but notably mepacrine, accelerate tumour growth, as monitored by Cox's statistical method for body weight, and lead to earlier death. In cases of existing neoplasia, therefore, the potentially toxic effects of certain antimalarials must be borne in mind.

Animals↗

Role of chemotherapeutic antagonism in opportunistic infections.

The most widely-known anti-tumor drugs often induce marked immunosuppression which can give rise to one or more sepses. Anti-infection measures immediately applied can sometimes prove largely ineffective or even useless, the patient dying not as a result of the spread of the tumour but as a direct consequence of opportunistic infection. We postulate that antagonism between anti-tumour and antimicrobial drugs may also play an important part in this. By way of illustration of this hypothesis, we have studied the action of a number of known inhibitors of peptidoglycan synthesis and of DNA-gyrases on certain strains of Gram-positive and Gram-negative microorganisms cultured in medium containing various concentrations of some of the best-known anti-tumour antimetabolites. The experimental data show that antimicrobial and anti-tumour drugs can sometimes induce synergic or indifferent chemotherapeutic interactions with many bacteria, while in others the effect is antagonistic. In practice, the action of the drugs could lead to bacterial selectivity, which, in conjunction with immunosuppression and the presence of resistant strains, could favour the evolution of opportunistic infection.

Anti-Bacterial Agents↗