PubMed Health⌕ Search

Biomedical subjects

M Perrin

Publications and source records attributed to M Perrin.

At least 109 records · Page 6Linked to original sources
PubMed1985

[Laboratory diagnosis of respiratory diseases of cattle].

The authors describe the procedure of laboratory diagnosis for bovine respiratory diseases: direct diagnosis by isolation and for identification of bacteria or viruses and indirect diagnosis by serological methods. They specify the restraints and limits of this diagnosis and the significance results which are obtained and connected with knowledge of anamnestic information.

Animals↗
PubMed1985

Growth hormone-releasing factor binding sites in rat anterior pituitary membrane homogenates: modulation by glucocorticoids.

Specific high affinity binding sites for growth hormone releasing factor (GRF) were described in rat anterior pituitary homogenates with use of the analog [His1-mono-125I-Tyr10,Nle27]-hGRF(1-32)-NH2 as radioligand. Computerized analysis of competition experiments indicated one class of specific high affinity binding sites with a dissociation constant of 0.19 nM. The relative binding affinities of rGRF, hGRF(1-40) and various analogs correlated well with their in vitro biological potencies. Further, the number binding sites was drastically decreased after adrenalectomy; chronic dexamethasone treatment of these animals restored GRF binding capacity to control without changing binding affinity. These results may in part explain the enhanced responsiveness of the somatotroph after dexamethasone treatment.

Adrenalectomy↗
PubMed1985

[Systolic pressure index at the ankle, a "beacon" of long-term monitoring of lower-limb arteriopathy].

Data is provided to demonstrate the reliability of measuring the systolic pressure index (SPI) for surveillance of lower limb arteriopathy (mainly during postoperative follow-up), the aim being to establish a simple, rapid and reliable surveillance test of high decisional value. Reproducibility of SPI values was studied in two series of patients (personal and collective) and on variations of SPI before and after reconstructive arterial surgery, as well as in cases of arterial bypass degradation. The following threshold values, beacon of the surveillance, were retained: --variations of 15% in relation to a reference examination: non-significant, --variations of 20 to 30%: probably significant, --variations of more than 30%: significant. A drop of 30% or more of the SPI in relation to a postoperative reference value during surveillance after reconstructive arterial surgery suggests the need for a follow-up angiography to detect possible lesions that could affect bypass permeability, whatever the patient's symptomatology.

Ankle↗
PubMed1985

[Clinical results of lumbar sympathectomy as a function of the amplification factor of Hillestad's reactive hyperemia test. Apropos of a series of 72 cases of isolated lumbar sympathectomies].

The efficacy of isolated lumbar sympathectomy was studied in 72 patients (36 with claudication, 36 with permanent ischemia) as a function of results of Hillestad's reactive hyperemia test (R.H.T.). Results were also assessed as a function of glucose tolerance, of the stage in Leriche and Fontaine's classification, of angiographic data, of certain pre-operative vascular function exploratory test parameters: systolic index at the ankle, digital pulsatility, segmental impedance plethysmography (irrigraphy), the tibial artery score and particularly the value for R.H.T. in the lower limb contralateral to the one for which sympathectomy was performed. Good results are very probable when the R.H.T. is positive or indifferent only in the lower limb for which sympathectomy is performed. Results were in fact better as the R.H.T. became more positive. Failure of treatment is very probable when the R.H.T. is indifferent in both lower limbs, particularly when the limb involved has an ankle systolic pressure lower than 0.25, an irrigraphic index lower than 0.10, the digital pulsatility has disappeared and the tibial artery score is 2/6 or less.

Aged↗
PubMed1983

Comparison of the effect of several gonadotropin releasing hormone antagonists on luteinizing hormone secretion, receptor binding and ovulation.

The biological activity of three gonadotropin releasing hormone (GnRH) antagonists was evaluated in the following assays: suppression of GnRH-mediated luteinizing hormone (LH) secretion by cultured pituitary cells, suppression of the spontaneous LH release by ovariectomized rats, blockade of ovulation in regularly cycling females and inhibition of binding of a potent radiolabeled agonist to rat pituitary membrane homogenates. The peptides were: [Ac-delta 3Pro1,4FDPhe2, DTrp3,6]-GnRH (Antagonist 1); [Ac-delta 3Pro1,4FDPhe2,DNAL(2)3,6]-GnRH (Antagonist 2); and [Ac-DNAL(2)2,4FDPhe2,DTrp3,DArg6]-GnRH (Antagonist 3). All three antagonists exhibited similarly high potency in suppressing LH secretion in vitro, while Antagonist 1 was the most active peptide in the radioreceptor assay. When administered by gavage, Antagonist 3 exhibited the highest potency to inhibit LH secretion in gonadectomized rats and to block ovulation. Comparison of the oral versus the subcutaneous mode of administration of these analogs indicates that less than 1% is absorbed after gavage. However, these data demonstrate that the intragastric administration of GnRH antagonists can lower gonadotropin secretion and interfere with reproductive functions.

Administration, Oral↗
PubMed1983

[Experimental infection of the pregnant cow with Chlamydia psittaci].

Seven cows were inoculated with two strains of C. psittaci from bovine origin. Their chlamydial excretion, complement fixing (CF) antibody titer and hormonal pattern, at calving or abortion were monitored. Five of the six pregnant inoculated cows had a pathological parturition, and a CF antibody titer greater than 40 during more than two months post-abortion. Three of them excreted Chlamydiae at calving. The other inoculated pregnant cow, the inoculated non pregnant cow and the three contacts had CF titer less than 40 during the same period. The progesteronemy and the oestradiol 17 beta level of the two early aborted cows were abnormal.

Abortion, Veterinary↗
PubMed1982

Pituitary somatostatin receptors: dissociation at the pituitary level of receptor affinity and biological activity for selective somatostatin analogs.

High affinity and saturable binding of [125I-Tyr11]somatostatin (SS) is described in membrane homogenates from a pituitary transplantable tumor (GH4C1) rich in somatotrophs (KD for SS = 0.67 nM; Bmax = 30 fmol/mg protein). Binding characteristics and pharmacology are similar to those measured on normal pituitary membranes. The potency of various SS analogs highly correlates with that measured in in vitro bioassay for growth hormone. This suggests that those GH4C1 membranes are a good model for SS receptors on somatotrophs. Interestingly however, analogs in which the Asn5 is deleted (Des-Asn5) or D-Ser replaces Ser13 show dissociated potencies between the various assays: [D-Ser13] analogs are more potent in pituitary than in GH4C1 membranes binding assay. Des-Asn5-modified analogs are much more potent in both pituitary binding assays than in the bioassay. This could reflect a multiplicity of SS receptor subtypes in pituitary.

Animals↗
PubMed1982

Specific high affinity binding sites for somatostatin-28 on pancreatic beta-cells: differences with brain somatostatin receptors.

Saturable and high affinity binding sites have been obtained for an iodinated somatostatin-28 (SS-28) analog, [Leu8,D-Trp22,125I-Tyr25] SS-28, in a membrane preparation from hamster insulinoma, mainly composed of pancreatic beta-cells. Specific binding is maximal after 1 hour incubation at 22C and represents 65% of the total binding. KD for [Leu8,D-Trp22,Tyr25] SS-28 is 0.25 nM with the number of sites corresponding to 68 fmol/mg protein. The KD for SS-28 (1nM) is more than 5 times lower than that for SS-14. SS-28 analogs, such as [D-Trp22] SS-28 and analogs which selectively inhibit insulin release in vivo (Des-Asn5[D-Trp8,D-Ser13] SS-14 and Des-Asn19[D-Trp22,D-Ser27] SS-28), are the most potent compounds in this assay. C-terminal replacement of L-cysteine by D-cysteine reduces the apparent affinity of SS analogs. Unrelated peptides and the inactive analog Des-Trp8-SS-14 have no affinity for insulinoma binding sites. There are differences between the insulinoma SS binding sites and those monitored under similar conditions from rat cerebral cortex. In cerebral cortex, SS-14 and SS-28 have similar affinity for the binding sites, and the insulin selective analogs are less potent than SS-14. It is concluded that pancreatic beta-cells, as well as brain, possess high affinity binding sites for SS, but that they differ in some of their pharmacological properties.

Adenoma, Islet Cell↗
PubMed1982

[Critical study and Doppler-arteriographies correlations in a homogeneous series of 115 examinations of the lower limbs (author's transl)].

Correlations between the results of Doppler and arteriographic examinations were studied in a series of 115 angiographies of the limbs, including global findings and 10 specific parameters of importance in vascular surgery. Overall results were strictly comparable in 70 % of cases. Detailed study of 1,150 parameters (10 x 115) revealed only 42 occasions (4 %) when Doppler and angiographic results could not be correlated. The percentage error for Doppler when compared with angiography examinations was of the order of 5 %, except for the tibial arteries when a 20 % error rate was found. Lack of correlation between Doppler and angiography findings could be of value for more precise determination of the tibial network.

Angiography↗
PubMed1980

[Ergotism of therapeutic origin. A report of 4 new cases (author's transl)].

The observations concern ischemic accidents with various localizations (lower limbs, tongue, uterus, intestine, heart, liver) corresponding to 4 observations for which ergot derivatives (ergotamine tartrate) can be responsible. The most typical accidents are localized at the level of limbs and especially of lower limbs. In the greatest part of observations, a specific terrain (puerperium, vasomotor disorders, suspicion of temporal arteritis) can be considered and favouring factors (infection, and especially associated medicinal treatments with triacetyloleandomycin [2 observations] and Doxycyclin [1 observation]). The posologies of ergot alcaloïds were either superior to the limit prescription or normal. The duration of prescription was variable, but generally short. The arteriography confirms a vascular spasm. In an observation with very severe evolution, various ischemic localizations inducing amputation, two intestinal resections and an hemodialysis for lactic acidosis were noted. These ischemic accidents have to be noticed as early as possible in order to start a treatment; the best one seems to be the association of sodium nitroprussiate in intravenous perfusion with peri-dural anesthesia in an antalgic aim.

Adolescent↗
PubMed1978

[Electromyographic silent period in the masseter and temporal muscles].

For some years, many authors have studied the silent periods (S.P.) in masticatory human muscles, during voluntary clenching, biting or mastication as well as during electrical or mechanical stimulation of various parts of the mouth. This S.P. appears as a flattening in the electromyograph tracing taken from masseter and temporalis anterior muscles simultaneously. After an analysis of the methods and results of previous authors, we give and discuss our result, obtained from records on masseter and temporalis anterior muscles, on right and left sides, on healthy subjects. They tapped first their teeth, then masticated pea-nuts, pieces of apple and soft bread. We obtained 571 S.P. after recording 1 745 cycles, and in contrary to the opinion of most of the authors, we were not able to obtain simultaneous S.P. in all four muscles at every cycle, except on 26 occasions. To conclude, we discuss our observations and suggest pathways for the inhibiting reflex of masticatory muscles during functions.

Adult↗
PubMed1977

[Cytotoxic and antitumor activity of a new series of heterocyclic compounds: dipyrido (4,3-b) (3,4-f) indoles].

Among newly synthesized compounds derived from the dipyrido [4,3-b] [3,4-f] indole nucleus, two have proved to be particularly active in vitro and in vivo. Their cytotoxic effects on cultured cells have been determined. At non toxic doses, they displayed a pronounced inhibitory effect on experimental L1210 Leukemia. These compounds have a strong affinity for DNA molecules.

Animals↗