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A Macaluso

Publications and source records attributed to A Macaluso.

29 records · Page 2Linked to original sources
PubMed1994

Central neurogenic antiinflammatory action of alpha-MSH: modulation of peripheral inflammation induced by cytokines and other mediators of inflammation.

The neuropeptide alpha-melanocyte-stimulating hormone (alpha-MSH) has potent antipyretic and antiinflammatory properties. When administered systemically, the naturally occurring molecule and its COOH-terminal tripeptide sequence inhibit inflammation induced by peripherally applied irritants and intradermal injections of mediators of inflammation such as interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF alpha). We recently found that alpha-MSH can act solely within the brain to inhibit inflammation caused by a general irritant applied to the skin. This activity appears to be shared with salicylate drugs and the combined observations suggest the existence of descending neurogenic antiinflammatory signals capable of modulating inflammation in peripheral tissues. To improve our knowledge of the scope of this action of the peptide, alpha-MSH was injected into the cerebral ventricles (i.c.v.) of mice that had received intradermal injections in the ear of mediators of inflammation: IL-1 beta, IL-8, leukotriene B4, and platelet-activating factor. The centrally administered peptide inhibited the actions of all of these proinflammatory agents as determined from comparisons with measures of ear edema over time in control animals; this indicates that the central peptide can alter inflammation induced in the periphery by major mediators of inflammation. In tests confined to IL-1 beta, central administration of alpha-MSH(11-13) was also effective. These findings support the concept of a descending neurogenic antiinflammatory influence promoted by an action of alpha-MSH within the brain, an inhibitory influence that is not restricted to modulation of just one or a limited set of the mediators of inflammation.

Animals↗
PubMed1994

Antiinflammatory influences of alpha-MSH molecules: central neurogenic and peripheral actions.

alpha-Melanocyte-stimulating hormone (alpha-MSH1-13) and its COOH-terminal tripeptide alpha-MSH11-13 (Lys Pro Val) inhibit inflammation when administered systemically. Recent evidence indicates that alpha-MSH1-13 can likewise inhibit inflammation in the skin solely via an action within the brain. Because of the potential importance of this discovery to understanding the control of inflammation and because alpha-MSH molecules might be useful for treatment of inflammation, experiments were performed to learn more about the mechanisms of action of these peptides. In tests on inflammation induced in the mouse ear by intradermal injections of recombinant human interleukin-1 beta, alpha-MSH1-1-13 administered intracerebroventricularly effectively reduced inflammation. This effect of centrally administered alpha-MSH1-13 was inhibited by systemic injection of the nonspecific beta-adrenergic receptor blocker propranolol and by administration of a specific beta 2-adrenergic receptor antagonist; the effect was not altered by blockade of cholinergic, alpha-adrenergic, or beta 1-adrenergic receptors. In mice with inflammation induced in a hind paw and with the spinal cord transected, the antiinflammatory effect of centrally administered alpha-MSH1-13 was prevented, indicating that intact descending neuronal pathways are required for the antiinflammatory influence of the central peptide. Systemic injection of alpha-MSH1-13 in animals with spinal cord transection had a smaller and later antiinflammatory effect, which suggests that the molecule also has an action, albeit lesser, in the periphery. However, alpha-MSH11-13 injected intraperitoneally had marked antiinflammatory activity in animals with spinal cord transection.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1991

Inhibition of acute inflammation in the periphery by central action of salicylates.

Understanding of the antiinflammatory actions of nonsteroidal drugs is incomplete, but these actions are believed to occur in the periphery, without any contribution from the central nervous system. Recent research on the antipyretic antiinflammatory neuropeptide alpha-melanocyte-stimulating hormone indicates that it can act centrally to inhibit peripheral inflammation; this raises the possibility that other agents, such as nonsteroidal antiinflammatory drugs, may have similar activity. In the present research both lysine acetylsalicylate and sodium salicylate inhibited edema, induced in the mouse ear by topical application of picryl chloride, when injected into the lateral cerebral ventricle. This inhibitory activity on a measure of acute inflammation was not due to escape of the drugs into the periphery, because systemic injection of doses that were effective centrally did not affect inflammation. In contrast, central administration of a dose of indomethacin that was antiinflammatory when given intraperitoneally did not inhibit peripheral inflammation. Thus indomethacin apparently lacks the central antiinflammatory action of the salicylates. This observation, plus our inability to demonstrate either an antiinflammatory effect of intracerebroventricular dexamethasone, a prostaglandin inhibitor, or a pro-inflammatory influence of prostaglandin E2, suggests that prostaglandins are not important to central modulation of inflammation. The results indicate that, in addition to having central influences on fever and pain, salicylates can act within the brain to inhibit acute inflammation in the periphery.

Animals↗
PubMed1991

Efficient transformation of Bacillus thuringiensis requires nonmethylated plasmid DNA.

The transformation efficiency of Bacillus thuringiensis depends upon the source of plasmid DNA. DNA isolated from B. thuringiensis, Bacillus megaterium, or a Dam- Dcm- Escherichia coli strain efficiently transformed several B. thuringiensis strains, B. thuringiensis strains were grouped according to which B. thuringiensis backgrounds were suitable sources of DNA for transformation of other B. thuringiensis strains, suggesting that B. thuringiensis strains differ in DNA modification and restriction. Efficient transformation allowed the demonstration of developmental regulation of cloned crystal protein genes in B. thuringiensis.

Bacillus thuringiensis↗
PubMed1990

Expression of Bacillus thuringiensis delta-endotoxin genes during vegetative growth.

Bacillus thuringiensis delta-endotoxin (crystal protein) genes are normally expressed only during sporulation. It is possible to produce crystal protein during vegetative growth by placing B. thuringiensis crystal protein genes downstream of a strong vegetative promoter. By removing a possible transcriptional terminator of the tetracycline resistance gene of pBC16 and inserting a multiple cloning site, delta-endotoxin genes can be cloned downstream from the tetracycline resistance gene promoter. This construct allows for readthrough transcription from the strong vegetative promoter. Crystal protein is then produced during vegetative growth as well as during sporulation in both B. thuringiensis and Bacillus megaterium. This construct also allows for production of delta-endotoxin in B. thuringiensis strains that do not normally produce delta-endotoxin because of a defect in sporulation.

Bacillus↗
PubMed1990

Role of the nac gene product in the nitrogen regulation of some NTR-regulated operons of Klebsiella aerogenes.

A positive, genetic selection against the activity of the nitrogen regulatory (NTR) system was used to isolate insertion mutations affecting nitrogen regulation in Klebsiella aerogenes. Two classes of mutation were obtained: those affecting the NTR system itself and leading to the loss of almost all nitrogen regulation, and those affecting the nac locus and leading to a loss of nitrogen regulation of a family of nitrogen-regulated enzymes. The set of these nac-dependent enzymes included histidase, glutamate dehydrogenase, glutamate synthase, proline oxidase, and urease. The enzymes shown to be nac independent included glutamine synthetase, asparaginase, tryptophan permease, nitrate reductase, the product of the nifLA operon, and perhaps nitrite reductase. The expression of the nac gene was itself highly nitrogen regulated, and this regulation was mediated by the NTR system. The loss of nitrogen regulation was found in each of the four insertion mutants studied, showing that loss of nitrogen regulation resulted from the absence of nac function rather than from an altered form of the nac gene product. Thus we propose two classes of nitrogen-regulated operons: in class I, the NTR system directly activates expression of the operon; in class II, the NTR system activates nac expression and the product(s) of the nac locus activates expression of the operon.

Amino Acid Transport Systems↗
PubMed1976

Glutamate dehydrogenase: genetic mapping and isolation of regulatory mutants of Klebsiella aerogenes.

The gene for glutamate dehydrogenase (gdhD) has been mapped in Klebsiella aerogenes by P1 transduction. It is linked to pyrF and trp with the order pyrF-trp-gdh. Complementation analysis using F' episomes from Escherichia coli suggests an analogous location in E. coli. Two mutants able to produce glutamate dehydrogenase in the presence of high levels of glutamine synthetase have been isolated. One, tightly linked to gdhD, shows normal repression control by glutamine synthetase but produces four times as much glutamate dehydrogenase activity as does the wild type under all conditions tested. The other revertant is not linked to gdhD or glnA.

Ammonia↗
PubMedDate not supplied

Central administration of the peptide alpha-MSH inhibits inflammation in the skin.

Inflammation is generally conceptualized in terms of cells, mediators, and events in the periphery, with no consideration of an influence of the central nervous system (CNS). However, the neuroendocrine peptide alpha-melanocyte stimulating hormone (alpha-MSH) is anti-inflammatory when given systemically and this molecule reaches the brain to exert another effect: fever reduction. Tests on mice indicate that alpha-MSH can act solely within the CNS to inhibit inflammation in the skin. This observation indicates that the central nervous system can inhibit peripheral inflammation via action of alpha-MSH molecules and it further strengthens the idea of neural/endocrine modulation of the host responses.

Animals↗
PubMedDate not supplied

[Virus transmission in drinking water].

Several epidemiological data confirm the presence of enteric viruses in drinking water. The present paper deals with several problems tied to the virological analysis, such as the concentration of the samples, the isolation and the identification of enteric viruses.

Drinking↗
PubMedDate not supplied

[Enteric viruses and bacteriological parameters in molluscs].

Eighty-seven samples of shellfish were collected considering: type of mollusc, origin, growing area, monitoring or for human purpose. The bacteriological parameters were: Fecal Coliforms, Escherichia coli, and Salmonella; whereas the virological parameters included: Hepatitis A and E virus, Rotavirus, Astrovirus and Enterovirus. In total, 63.2% of samples had normal bacteria values, only one sample was Salmonella positive. The percentage of positive samples for Hepatitis A virus was 5.7%, Rotavirus 29.9%, Astrovirus 27.6%, Enterovirus 10.3%. The recovery of hepatitis E virus was always negative, whereas 13 samples (14.9%) were positive for two viruses.

Animals↗