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Biomedical subjects

J Daniel

Publications and source records attributed to J Daniel.

At least 91 records · Page 5Linked to original sources
PubMed1982

crpX mutants of Escherichia coli K12: specific regulatory effects of altered cyclic AMP receptor proteins.

We attempted to correlate structural modifications of the adenosine 3',5' cyclic monophosphate (cAMP) receptor protein (CAP), to changes in some of its in vivo regulatory functions such as (i) stimulation of the lactose operon expression and (ii) control of adenylate cyclase activity. A radioimmunological procedure was used to study the structure of CAP synthesized by three mutants (crpX) grown under various conditions, in the presence or absence of endogenous or exogenous cAMP. In one mutant CAP appears to be sensitive to thermal inactivation. In another mutant CAP is particularly sensitive to degradation in the absence of cAMP; this degradation is enhanced by high temperature and during stationary phase of growth, and prevented by the addition of glucose. Functional alterations of CAP were not found to follow structural changes strictly. In the crpX mutants and in strains carrying the crp+ or other crp allele, the stimulation of the lactose operon expression and the modulation of the in vivo rates of cAMP synthesis appear to vary in parallel, favoring an indirect mechanism of regulation of adenylate cyclase by CAP.

Adenylyl Cyclases↗
PubMed1982

Attenuation in the threonine operon: effects of amino acids present in the presumed leader peptide in addition to threonine and isoleucine.

We have studied in vivo the contribution of amino acids corresponding to codons of the leader sequence other than the so-called "regulatory codons" (for threonine and isoleucine) in the expression of the threonine operon. In the presence of threonine and isoleucine, addition of each amino acid encoded in the proximal part of the leader sequence resulted in a significant decrease of the expression of the operon, over and above that decrease observed in the sole presence of threonine and isoleucine. These effects were cumulative. No such effect was found with the amino acids encoded by the distal part of the leader sequence. These findings are discussed in the light of the current model of attenuation.

Amino Acid Sequence↗
PubMed1980

New technique of total pancreatectomy without duodenectomy in the dog.

Total pancreatectomy without duodenectomy is described in the dog. The technique is based on the recognition of an anatomic cutting line between the two peritoneal layers overlying the duodenopancreas in the dog. This allows selective suppression of the pancreatic vascular supply and anatomic dissection between the pancreas and the duodenum. Complete pancreatectomy is indicated by hyperglycemia, absence of detectable serum insulin, abnormal glucose tolerance tests and short survival time due to metabolic conditions. No surgical complication was noted, and this reliable model is proposed for experimental pancreatic transplantation studies.

Animals↗
PubMed1980

Plasma noradrenaline concentration in essential hypertension during long-term beta-adrenoceptor blockade with oxprenolol.

1. Chronic beta-adrenoceptor blockade with oxprenolol causes elevation of plasma noradrenaline levels, as compared with placebo, despite a significant fall in blood pressure and pulse rate. 2. The plasma noradrenaline concentration is not influenced by the frequency of administration or the formulation of the drug. 3. Plasma noradrenaline levels are not correlated with the plasma concentration of the drug. 4. The changes in plasma noradrenaline concentrations support a peripheral rather than central mechanism of action of beta-adrenoceptor blockers in man.

Adult↗
PubMed1979

Involvement of cyclic AMP and its receptor protein in the sensitivity of Escherichia coli K 12 toward serine: excretion of 2-ketobutyrate, a precursor of isoleucine.

A relationship between serine-induced growth sensitivity and the cAMP-CAP complex is established. Mutants of Escherichia coli K 12 deficient either in the cya or crp gene function exhibit a resistant phenotype on serine media although they harbor a relA allele normally leading to sensitivity toward serine. The presence of a crp allele in a cya delta relA background restores the sensitivity phenotype, while the analysis of serine resistant mutants selected from a crp cya delta relA strain shows that the mutation leading to resistance is located at, or very near, the crp gene, giving a more or less Crp- phenotype. In addition crp cya delta relA strains excrete large quantities of 2-ketobutyrate when grown on glucose M63 medium. This excretion is unambiguously linked to the presence of the crp allele and is correlated with an enhanced threonine deaminase activity. Besides, the complex regulation exerted on the acetolactate synthase activities is discussed.

Butyrates↗
PubMed1977

Minoxidil in resistant hypertension.

Minoxidil in combination with propranolol and diuretics controlled the blood-pressure in a group of hypertensive patients who were resistant to treatment with large doses of standard drugs. The main problem was fluid retention but subjective side-effects were fewer than in a comparable group on other drugs.

Blood Pressure↗
PubMed1977

Eye symptoms in patients taking propranolol and other hypotensive agents.

1 Four hundred and eighty-three hypertensive patients being treated with propranolol or other hypotensive drugs were questioned about symptoms of gritty feelings, sore or red eyes, photophobia and use of eye drops. 2 Between 11.6% and 29.8% gave positive answers but there was no difference between the different drug regimes. The complaint of 'red eyes' was more common in smokers.

Antihypertensive Agents↗
PubMed1977

[Toxic staphylococcal cutaneous necrolysis (scalded skin syndrome) (author's transl)].

The exfoliating exotoxin of serotype II staphylococci is responsable of three diseases with prevailing dermatologic symptoms: staphylococcal scarlet fever, staphylococcal Lyell syndrom and Ritter-Lyell disease. Melish demonstrated the effect of staphylococcal exotoxin on new-born mice less than five days old. This experimental model allowed to study the characteristics of the toxin. Precocious antistaphylococcal antibiotherapy is necessary.

Animals↗
PubMed1976

[Collodion baby. Clinical course based on 29 cases].

Study of 29 cases of collodion baby and 169 cases previously published led to several conclusions. In the short-term, the child is threatened by pulmonary infections. The increased skin permeability may result in the loss of water or intoxication by cutaneous absorption of a substance applied to the skin. In the long-term the condition progresses to one of a congenital disturbances in keratinisation. In 2/3 of cases, the problem is that of congenital non-bullous ichthyosiform erythrodermia. Profression to lamellar ichthyosis, ichthyosis vulgaris, circumflex linear ichthyosos and Conradi's syndrome is established. Ichthyosis related to sex in our cases did not seem to be a feature of the collodion baby, the opinion in the literature being divergent. Congenital bullous ichthyosiform erythrodermia never begins as collodion baby syndrome.

Adolescent↗