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D Allain

Publications and source records attributed to D Allain.

At least 19 recordsLinked to original sources
PubMed2006

A first-generation microsatellite-based integrated genetic and cytogenetic map for the European rabbit (Oryctolagus cuniculus) and localization of angora and albino.

Although the European rabbit (Oryctolagus cuniculus) is used both in agronomics and in research, genomic resources for this species are still limited and no microsatellite-based genetic map has been reported. Our aim was to construct a rabbit genetic map with cytogenetically mapped microsatellites so as to build an integrated genetic and cytogenetic map. A reference population of 187 rabbits comprising eight three-generation families with 10-25 offspring per family was produced. One hundred and ninety-four of 305 previously identified microsatellites were included in this study. Of these, 158 were polymorphic with two to seven alleles. The map reported here comprises 111 markers, including 104 INRA microsatellites, five microsatellites from another source and two phenotypic markers (angora and albino). Ninety markers were integrated into 20 linkage groups. The remaining 21 microsatellites mapped to separate linkage groups, 19 with a precise cytogenetic position and two with only a chromosomal assignment. The genetic map spans 2766.6 cM and covers 20 rabbit chromosomes, excluding chromosomes 20, 21 and X. The density of this map is limited, but we used it to verify the location of angora and albino on chromosomes 15q and 1q, respectively, in agreement with previously published data. This first generation genetic/cytogenetic map will help gene identification and quantitative trait loci mapping projects in rabbit.

Alleles↗
PubMed1986

Effects of pinealectomy on photoperiodic control of hair follicle activity in the Limousine ram: possible relationships with plasma prolactin levels.

Twelve adult Limousine rams (five pinealectomized, four sham operated, and three control) were housed under an artificial lighting regime of alternating periods of long (16L:8D) and short (8L:16D) days for 18 months, and long-term variations in kemp follicle growth were recorded along with measurements of the plasma prolactin concentrations. In control and sham-operated rams, both parameters varied in relation to imposed lighting regime. Moult and growth of the kemp follicles occurred during each short-day period at a time when the concentrations of prolactin were low and vice versa. Variations in the pinealectomized rams were different from those in the control or sham-operated ones. There was no synchronous periodic kemp activity: some follicles remained active at all times, and the seasonal pattern of plasma prolactin levels disappeared. The relationship between the kemp follicle cycle and the pattern of plasma prolactin concentrations and its control by the pineal gland are discussed.

Animals↗
PubMed1985

Role of the pineal gland in the photoperiodic control of reproductive and non-reproductive functions in mink (Mustela vison).

Mink are long-lived mammals that exhibit seasonal changes in body weight, gonadal activity, pelage and plasma prolactin levels. Mating in February-March is followed by an obligatory delay in implantation during which the corpora lutea stay quiescent. All these events are controlled by annual variations in daylength. The role of the pineal gland and its product, melatonin, in conveying photic information to the target organs has been studied. Pineal denervation by bilateral ablation of the cervical superior ganglia rendered the mink unresponsive to artificial manipulations of the daily photoperiod: prolactin and progesterone secretion and the spring moult were no longer stimulated by long days or inhibited by short days in pregnant females; in the same way the increase in body weight in late summer and the autumn moult were no longer advanced by artificial shortening of the photoperiod. Pinealectomy seemed to desynchronize body weight, prolactin and moulting cycles from those in intact mink. Melatonin injections reproduced the effects of short days on hormonal secretion during the delayed implantation period. Melatonin capsules given to males during the phase of testicular activity delayed the decrease in body weight, testicular regression and onset of the spring moult exactly as did short days. In contrast, melatonin administered during the phase of testicular inactivity triggered an increase in body weight, the onset of the spring moult and testicular recrudescence in this short-day breeder. These results support the hypothesis that in mink all photoperiodic signals are conveyed by the pineal gland. But although the pineal seems essential for the seasonal timing of the cycles, it does not modify the events themselves once they are initiated.

Animals↗
PubMed1985

Pineal denervation by cervical sympathetic ganglionectomy suppresses the role of photoperiod on pregnancy or pseudopregnancy, body weight and moulting periods in the mink (Mustela vison).

In mink, termination of the delayed implantation period, following reactivation of the corpora lutea, and onset of the spring moult are associated with a rise in prolactin secretion triggered by increasing daylength, while decreasing daylength induces the autumn moult. To establish whether suppression of the function of the pineal rendered the mink unresponsive to daylength changes, the superior cervical ganglion was removed bilaterally 2-4 weeks before mating. Intact and operated females were then left outdoors or were put under a lighting regime of either 15 h light:9 h darkness (15L:9D) or 8L:16D. In July, at the end of the spring moult, the 15L:9D lighting regime was changed to one of 8L:16D. Under artificial photoperiods ganglionectomy suppressed the stimulatory role of long days and the inhibitory role of short days on prolactin secretion, and consequently on progesterone secretion and spring moult. Neither was the autumn moult, induced early in intact females by the change to a short photoperiod, advanced in ganglionectomized females, showing that the latter were unresponsive to the artificial modification of the photoperiod. However, in animals kept outdoors, prolactin and progesterone secretion and spring moult were not changed by ganglionectomy. Increase in body weight and autumn moult were only slightly delayed by the operation suggesting that other environmental factors had replaced the synchronizing effect of the daylength changes. Alternatively the desynchronization between intact females responsive to photoperiodism and those rendered unresponsive may be too slow to be observed soon after ganglionectomy.

Animals↗
PubMed1985

Human and sylvatic Trypanosoma cruzi infection in California.

In August 1982, a 56-year-old woman from Lake Don Pedro, California, developed acute Chagas' disease (American trypanosomiasis). She had not traveled to areas outside the United States with endemic Chagas' disease, she had never received blood transfusions, and she did not use intravenous drugs. Trypanosoma cruzi cultured from the patient's blood had isoenzyme patterns and growth characteristics similar to T. cruzi belonging to zymodeme Z1. Triatoma protracta (a vector of Trypanosoma cruzi) infected with T. cruzi were found near the patient's home, a trypanosome resembling T. cruzi was cultured from the blood of two of 19 ground squirrels (Spermophilus beecheyi), and six of 10 dogs had antibody to T. cruzi. A serosurvey of three groups of California residents revealed antibody to T. cruzi by complement fixation in six of 237 (2.5 per cent) individuals living near the patient and in 12 of 1,706 (0.7 per cent) individuals living in a community 20 miles northeast of the patient's home, but in only one of 637 (0.2 per cent) blood donors from the San Francisco Bay area. This is the first case of indigenously acquired Chagas' disease reported from California and the first case recognized in the United States since 1955. This investigation suggests that transmission of sylvatic Trypanosoma cruzi infection to humans occurs in California but that Chagas' disease in humans is rare.

Adolescent↗
PubMed1984

Role of prolactin in the photoperiodic control of moulting in the mink (Mustela vison).

Beginning at the summer solstice adult female mink were maintained in long- or short-day photoperiods and treated with bromocriptine or prolactin. In control females kept under natural lighting conditions the moult coincided with the seasonal decrease in prolactin and resulted in the growth of a dense winter coat which was completed by the end of November. Long days, which slowed the decrease in plasma prolactin relative to animals in the natural photoperiod, induced a more or less complete moult followed by growth of a thin summer coat. On the contrary we observed an accelerated decrease in plasma prolactin concentrations followed by an early and brief moult in females kept under long days but treated with bromocriptine and in females under short days. The growth of a dense winter coat was completed by the end of September in all the females of the short-day group and in six of eleven females treated with bromocriptine. In the other five females, moult was followed by the growth of a summer coat. These results may suggest that the decline of prolactin after the summer solstice is responsible for the onset of the autumn moult, but the early, abbreviated moult and the growth of a winter coat observed in females kept under short days and treated with prolactin do not seem to support this hypothesis. However, the huge non-physiological levels of prolactin measured in the plasma of these females and the appearance of abnormal white under-hairs might suggest that the hormonal balance in this group was completely disturbed by the treatment. The physiological role of prolactin in the seasonal moulting cycle in mink is discussed.

Animals↗
PubMed1981

[Irradiation of the thymus region in chronic lymphoid leukaemia. Seven cases (author's transl)].

7 patients with chronic lymphatic leukemia, B type, have been treated with thymic irradiation. A full remission was achieved in 2 and a partial one in 4. No serious complications were noted during or after the irradiation. This treatment has proved efficient even after the failure of a previous chemotherapy and has permitted to resume any other therapeutic modality when the C.L.L. is no more controlled.

Aged↗
PubMed1980

Induction of autumn moult in mink (Mustela vison Peale and Beauvois) with melatonin.

Adult female mink, living in natural conditions of temperature and photoperiod, were treated by melatonin implants in mid-July, when the summer coat was in its resting stage. As a result, a moult was induced 5 to 6 weeks before the normal time; its showed the characteristics of an autumn moult as observed by the gradient of hair changes over the body and the high number of hair follicles per bundle (47 p. 100 more than in the summer coat). The winter coats produced in this way were mature in the early days of October, i.e. 6 to 7 weeks before those of the control group.

Animals↗
PubMed1977

[Early diagnosis of respiratory distress in premature infants. Application of the Clements test to the gastric fluid].

The stomach of the newborn infant contains swallowed amniotic fluid. The gastric fluid of 66 newborn infants was placed in contact with alcohol, following the technique reported by Clements in relation to amniotic fluid. The stability of the bubbles formed after mixing correspond to the presence of surfactant. In the case of respiratory distress in a premature infant, a positive test is in favour of transient respiratory distress. Intermediate or negative results are seen essentially in the presence of idiopathic respiratory distress. Application of the Clements test to gastric fluid collected immediately after birth is an excellent mean of diagnostic orientation in the presence of early respiratory problems in a premature infant. When negative, the child should be transferred to a specialised centre in order that intermittent positive pressure therapy may be started, the effectiveness of the latter being related to how soon it is begun.

Amniotic Fluid↗
PubMed1977

[Islet cell adenoma with neonatal onset. Clinical, hormonological and ultrastructural study of a case].

A case of hyperinsulinism occuring in a newborn, with a birthweight of 4,050 g, is reported. The hypoglycaemia was refractory to the usual therapy (increase of glucose administration per os, and I.V., corticosteroids, glucagon, diazoxide). At surgery, undertaken at 9 days of age, an adenomatous nodule was removed along with the left part of the pancreas. Death occurred at 18 days, after the child had developed a transitory acidoketosic diabetes and an encephalopathy. Measurement of insulin by radio-immunoassay revealed a strong increase in the ratio insulin/glycaemia, characteristic of nesidioblastoma, as well as a high concentration of insulin in the tumor as compared to normal tissue. On the ultrastructural level, the observed features differed from those seen in children and adults and showed an abnormal overload of dense deposits in the cytoplasm of some histiocytes.

Adenoma, Islet Cell↗
PubMed1977

[Adrenal cysts in the newborn. Apropos of 2 cases].

Cysts of the adrenal gland are very rare in the neonatal period and are always diagnosed either at surgery or at autopsy. Two patients are reported. One is an infant born at term in whom a mass in the left loin was discovered on the 3rd day of life. At surgery a suprarenal tumour was discovered and a polycystic adrenal was removed: recovery was uneventful. Histology showed a cystic haemangioma in the adrenocortical tissue. The diagnosis made was that of a cystic haemangioma. The other patient is an infant born at 38 weeks gestation who became jaundiced and developed a haemolytic streptococcal septicaemia. A mass was found in the right lumbar region on the 3rd day. The calcified egg-shell appearance, renal arteriography and an intravenous pyelogram demonstrated the cystic appearance of the adrenal. The cystic mass and the adrenal gland were removed and the patient recovered. Histological examination suggested that a pseudocyst had arisen secondary to a haemorrhagic infarct caused by a septic embolus. Adrenal cysts are classified as true cysts and pseudocysts (which must be distinguished from unilateral haematomas). The histological appearances are reviewed. These patients may be added to the 11 neonatal case reports in the literature (9 haemorrhagic pseudocysts, only 2 true cysts). To our knowledge cystic haemangioma has not previously been reported.

Adrenal Gland Diseases↗