Search PubMed⌕ Search

Biomedical subjects

D Boucher

Publications and source records attributed to D Boucher.

At least 73 records · Page 4Linked to original sources
PubMed1992

A method for cytogenetic analysis of boar spermatozoa using hamster oocytes.

In this paper, the authors detail a method for displaying boar spermatozoa chromosomes using heterospecific zona-free hamster oocyte penetration technique. Semen samples from two Large-White boars having a normal spermogram were studied. The first one had a normal karyotype (38,XY), the second carried a reciprocal translocation rcp(3;7)(p1,3;q2,1). After in vitro fertilization by capacitated sperm, culture and cytogenetic analysis of hamster eggs we obtained metaphase spreads of spermatozoa chromosomes. The ratio of X- and Y-bearing spermatozoa was 49.2% and 50.8%, respectively.

Animals↗
PubMed1991

[A support group intended for women victimized by conjugal violence].

For battered women, leaving the home and spending time in a shelter is only the first step of a long process of change that usually involves periodic crises. A support group has been set up to help these women establish new ways to relate with the outside world, ways that are meant to assist them in successfully going through this difficult phase of their lives. Based on Lifton's principles of affinity, presence and consolidation (1976), the authors highlight the value of reciprocity in the therapeutical relationship. In addition, the authors discuss issues relating to the main points affecting interventions with battered women who have spent time in a shelter.

Crisis Intervention↗
PubMed1990

Influence of the pineal gland on testicular function in offspring of pinealectomized rats.

Female Sprague-Dawley rats exposed to a short (6L:18D) photoperiod from 21 days of age were mated when they reached 55 days of age. On Day 2 of gestation animals were pinealectomized or sham-operated. On Day 5 after birth male pups of the two groups of dams were either pinealectomized or sham-operated. They were killed at 42 and 49 days of age. In offspring born to sham-operated dams and in those born to pinealectomized mothers, neonatal pineal ablation resulted in increased testicular testosterone and androstenedione content. In sham-operated and neonatally pinealectomized rats removal of the maternal pineal gland induced a decrease in testicular testosterone and androstenedione content. In contrast, after maternal pinealectomy there was a decrease in plasma testosterone and dihydrotestosterone values and testicular dihydrotestosterone content in sham-operated rats but not in those neonatally pinealectomized. We conclude that (1) the pineal glands of the mother and offspring are required to maintain normal testicular testosterone and androstenedione content in the rat, and (2) the pineal of the offspring influences the inhibitory effects of maternal pinealectomy on testicular dihydrotestosterone content and on plasma testosterone and dihydrotestosterone concentration in the offspring.

Androstenedione↗
PubMed1990

Expecting excellence is key to receivable success in small and rural hospitals.

Although small and rural hospitals may have trouble hiring experienced billing and collection personnel, they can succeed in keeping down receivable levels and receivable days by adopting two principles for the business office: expect excellence and inspect for excellence. These principles include setting goals for business office staff as well as listening to and implementing their ideas for more effective operations.

Accounting↗
PubMed1989

Studies on the control of gene expression of the carcinoembryonic antigen family in human tissue.

The control of expression of genes of the carcinoembryonic antigen family was investigated in 22 specimens of malignant and nonmalignant human colonic tissues. These surgical specimens included seven colonic adenocarcinomas that were compared with normal adjacent colonic mucosal tissues from the same individual. mRNA preparations from all colonic tissues expressed three bands of 3.5, 3.0, and 2.6 kilobases on Northern blots probed with carcinoembryonic antigen (CEA) complementary DNA probe while normal liver and spleen were negative. The major band of 3.0 kilobases was 6 to 10 times more intense in the colon tumor specimens than in the matched normal mucosa. However, the tumor/normal ratios of immunoreactive CEA in these pairs varied from 2- to greater than 100-fold. Furthermore, there was no direct proportionality between mRNA levels and gene product expression, suggesting that the known variations in CEA expression in human colonic tissues result from both transcriptional and posttranscriptional control mechanisms. Southern blots of DNA from these specimens did not reveal any gene rearrangements or amplifications accompanying expression. Finally, Southern blots of DNA digested with methylation-sensitive endonucleases and probed with a genomic DNA fragment upstream of CEA gene coding regions demonstrated that CEA expression is correlated with a decreased level of methylation in the 5' region of the CEA gene.

Adenocarcinoma↗
PubMed1989

Ultrastructural and immunohistochemical evidence of in situ differentiation of mononuclear phagocyte system cells in the interstitium of human fetal testis.

Ultrastructural and immunohistochemical studies were made of the testicular interstitial tissue from eight human fetuses of 15 to 27 weeks gestation. Three cell types developed in mesenchymal cells: Leydig cells and peritubular cells, as already reported, and cells of the mononuclear phagocyte system (MPS), which are located in the intermediate area of the interstitial tissue. Located at the periphery of Leydig cells, these gradually differentiate between 16 and 20 weeks and later acquire the ultrastructural characteristic of histiocytes during the involution phase of the fetal testis. Immunohistochemical studies using monoclonal antibodies (Mo Ab) to antigens of human myelomonocytic cells isolated a cell subpopulation in the interstitial tissue that is distinct from the peritubular (fibroblastic) and the Leydig cells. This subpopulation expressed all or some of these antigens according to their stage of differentiation; all cells are labelled by MY7 Mo Ab which is directed against myelomonocytic cells, including stem cell. Using monoclonal antibodies directed against more mature cells (MY4, MO1 and MO2), the number of labelled cells decreased in this mesenchymal population. MY4 Mo Ab, which detect myelomonocytic cells excluding stem cell, label fewer than MY7 Mo Ab. MO1 MO Ab and MO2 Mo Ab, respectively, directed against antigens of more mature or mature monocytic cells, label less number of mesenchymal cells, which are histiocytes after 20 weeks. These ultrastructural and immunohistochemical findings suggest that cells of the MPS differentiate within the interstitium.

Antibodies, Monoclonal↗
PubMed1989

Aromatase activity in purified Leydig cells from adult rat. Comparative effects of insulin, IGF-I, and hCG.

The comparative effects of insulin and IGF-I on aromatization in adult rat purified Leydig cells were examined to elucidate the mechanism of action of the peptides in testicular steroidogenesis. Aromatase activity was measured in short-time incubations, using the tritiated water release method with [1 beta-3H] and androstenedione as substrate. In the presence of varying concentrations of substrate, the apparent Km for androstenedione was 0.945 mol/l; treatment of cells with insulin, IGF-I and hCG markedly increased the apparent maximal velocity, without modifying Km; peptides were more potent in aromatase stimulation than hCG alone or in combination with either peptides. When related to time (0-4 h) and expressed as percent of control values, aromatase activity in the presence of insulin, IGF-I and/or hCG exhibited a significant and transient increase at 15-30 min. In order to clarify the nature of this early stimulation, the effects of dibutyryl cAMP, various antibiotics, and cytochalasin B on treated Leydig cells were analysed. Results indicated that insulin and IGF-I action on aromatization was not cAMP-dependent; peptides could intervene by increasing RNA and protein, but not DNA, synthesis; they were also effective in glucose transport. These data suggest that insulin and IGF-I are able to modulate aromatization in Leydig cells.

Animals↗
PubMed1988

Transcription of genes of the carcinoembryonic antigen family in malignant and nonmalignant human tissues.

Normal and diseased human tissues were analyzed for the transcription of genes of the carcinoembryonic (CEA) family. Epithelial tissues of colonic origin, whether malignant or normal, all express two closely related mRNA species of 3.0- and 3.5-kilobase mRNA which code for CEA. Only tissues of colonic origin were found to express these CEA-specific transcripts. Colon carcinomas consistently express a 2.6-kilobase mRNA species as well which codes for nonspecific cross-reacting antigen. Nonneoplastic colon mucosas, on the other hand, express lower or nondetectable levels of this transcript. Most breast carcinomas produce only the nonspecific cross-reacting antigen mRNA, whereas leukocytes of chronic myelogeneous leukemia express both nonspecific cross-reacting antigen mRNA and a 2.3-kilobase mRNA corresponding to a yet undefined gene of the CEA family. Thus the multiple CEA-like products reported to be produced by these tissues correspond to only four different mRNA species coding for three different peptides. These data suggest a less complex organization of the CEA family than was previously suspected and point to posttranscriptional modifications, such as variable patterns of glycosylation, as the likely reason for much of the observed complexity in CEA-like glycoproteins.

Carcinoembryonic Antigen↗
PubMed1988

Evidence of 3 beta-hydroxysteroid dehydrogenase activity in several murine embryonal carcinoma cell lines.

This report describes, for the first time to our knowledge, a possible steroidogenic activity in established murine embryonal carcinoma cell lines (PCC3, PCC4, F9), revealed by a 3 beta-hydroxysteroid dehydrogenase activity (revelation of NADH2 by staining, and RIA assessment of delta 4-androstenedione). The remarkable analogy between such totipotent cells and embryonal cells may suggest that this activity could be present before histologic organization of the embryonal testis. Nonmalignant embryonal cells such as fibroblasts (3/A/1/D-3) or myoblasts (T984) were also found to possess a 3 beta-hydroxysteroid dehydrogenase activity, thus suggesting that this enzyme is not specific to hormone-secreting cells, but the sign of a more general phenomenon.

3-Hydroxysteroid Dehydrogenases↗
PubMed1988

Light and electron microscopic immunolocalization of two nuclear antigens in the liver of Pleurodeles waltl using monoclonal antibodies.

The distribution of 2 nuclear antigens in the interphase nuclei of liver of Pleurodeles waltl was determined with the help of monoclonal antibodies, using immunofluorescence for light microscopy and indirect immunoperoxidase and immunogold labeling procedures for electron microscopic localization. The antibodies C36/1 and A33/22 label antigens with relative molecular masses of 270 kDa and 80 kDa, and isoelectric points of 7.0 and 6.4, respectively. The liver of urodels is characterized by the presence of a peripheral layer of hematopoietic cells around the parenchymatous tissue formed by typical hepatocytes. The antibody C36/1 labels the nuclei of both types of cells, whereas the antibody A33/22 labels the nuclei of hepatocytes but not those of the peripheral hematopoietic cells. With both these antibodies, labeling, whenever observed, is restricted to fibrillar structures in the interchromatin space, i.e., to peri- and inter-chromatin fibrils; condensed chromatin, nucleoli, and nuclear envelope are not labeled.

Animals↗
PubMed1988

Characterization of insulin binding and comparative action of insulin and insulin-like growth factor I on purified Leydig cells from the adult rat.

Insulin binding and insulin action were characterized in adult rat Leydig cells, purified on discontinuous Percoll gradients. Binding of [125I]-porcine insulin was found to be dependent on time, temperature, cell concentration and Leydig cell specific gravity. Competition relative to porcine insulin (100) was as follows: insulin-like growth factor I (IGF-I) : less than 1; proinsulin : 5; guinea-pig insulin : 2; hCG, ovine prolactin and bovine GH : 0. High and low affinity binding sites for insulin were identified on purified Leydig cells with Ka values of 1.2 X 10(9) and 0.3 X 10(8) M-1, with 10,300 and 34,000 binding sites per cells, respectively. Using primary cultures of Leydig cells in serum-free medium, the action of insulin on steroidogenesis was studied and compared with IGF-I action. Insulin and IGF-I used at 1-35 nM enhanced basal testosterone production in a dose-dependent manner; the effect was significant 4 h after administration. Insulin or IGF-I also potentiated the effect of hCG on steroidogenesis during short-term incubation (4 h). Insulin was shown to improve hCG responsiveness without modifying sensitivity to hCG. Moreover, neither cell number nor hCG-binding was altered by insulin, IGF-I or a combination of the two. Concomitant treatment with insulin and IGF-I at half-maximal and maximally effective doses, in the presence or absence of hCG, indicated that the two factors synergized in the stimulation of testosterone production via a common saturable mechanism.

Animals↗
PubMed1987

Testosterone, androstenedione, progesterone and 17 alpha-hydroxyprogesterone in plasma and testes of immature rats under basal conditions and after hCG stimulation. Effect of bilateral cryptorchidism.

Rats were made bilaterally cryptorchid at 21 days of age; sham-operated rats were used as controls. At 35 days, the animals were injected i.m. with saline or with 10 IU hCG. Progesterone, 17-hydroxyprogesterone, androstenedione and testosterone were measured in both testes and plasma under basal conditions and 2, 4, 8, 12, 24 and 72 h respectively after injection. The plasma levels and intratesticular contents of the steroids were generally lower in cryptorchid rats. The patterns of the steroid response to hCG were similar in both groups: in the testes and in the plasma, they increased acutely following hCG injection (except testicular androstenedione), then, after 72 h, returned to normal values in the plasma but remained higher than the basal values in the testes. These results suggest that there are no gross abnormalities in the testicular steroidogenic pathways and that the mechanism of action of hCG on the Leydig cells is unaltered in bilaterally cryptorchid immature rats.

17-alpha-Hydroxyprogesterone↗
PubMed1987

Effect of mefenamic acid on bronchial tone in vivo.

Prostaglandins (PG) are very potent mediators which can dilate or constrict the bronchi. In order to evaluate the role of PG in the homeostasis of bronchial tone, we studied the effects of mefenamic acid, a potent cyclooxygenase inhibitor, on the pulmonary function tests of 20 volunteers. The subjects were studied randomly in two sessions, one with a placebo and one with mefenamic acid. Tablets (drug or placebo) were taken for 2 days with the pulmonary function tests performed in the afternoon of the second day. Sessions were performed at least 2 days apart. Parameters measured, including forced vital capacity, forced expiratory volume in 1 s, expiratory flows, functional residual capacity and specific airway conductance (SGaw), were similar in both sessions. The SGaw, which was previously reported to increase with cyclooxygenase inhibitors, was 0.23 +/- 0.06 s-1 X cm H2O-1 in the placebo session and 0.24 +/- 0.06 in the mefenamic acid session (mean +/- SD). This study shows that cyclooxygenase inhibitors have no effect on airway tone and strongly suggests that endogenous PG do not participate in the homeostasis of normal bronchial tone.

Adolescent↗
PubMed1987

Gonadal function in male offspring of pinealectomized female rats.

Female rats were exposed to a short (6 L: 18 D) photoperiod from 21 days of age. On day 2 of gestation, animals were pinealectomized sham-operated. Lighting regimens were not changed during the course of the study. Male offspring of the 2 groups of rats were sacrificed on days 30, 42 and 49 after birth. Pinealectomy of the mother induced the following modifications: in 30-day-old offsprings, a decrease in prostatic weight and plasma dihydrotestosterone level; in 42-day-old rats, a decrease in prostatic weight, in testicular androstenedione and dihydrotestosterone content, and in plasma testosterone and dihydrotestosterone levels; in 49-day-old animals, decreased testicular and plasma testosterone and dihydrotestosterone levels. These results indicate that rat testicular function, after exposure to a short photoperiod beginning before conception, is decreased by maternal pinealectomy. The mother's pineal gland may play a part in the control of rat testicular function.

Androstenedione↗
PubMed1986

[Takayasu's disease. Value of digital intravenous angiography. 44 cases].

Forty-four patients with Takayasu's arteritis were explored by digital intravenous angiography either for diagnostic purposes and pre-therapeutic assessment (n = 29) or immediately after surgery (n = 15). There were 36 women, 6 men and 2 children; mean age was 31 years. The contrast medium (mean volume 140 ml) was injected into central (74%) or peripheral (26%) veins. No other angiographic exploration was contemplated in 24 patients selected for medical treatment. Among 15 patients destined to surgery or percutaneous angioplasty, 13 were operated upon without further angiography and 2 underwent arteriography since the distal vascular bed beyond the major lesions could not be evaluated adequately. Data obtained from post-operative evaluation (n = 15) were satisfactory, with 1 failure in this group. Digital intravenous angiography seems to be reliable enough to be used as first examination in patients with suspected Takayasu's arteritis. The procedure is well tolerated and can be repeated for optimum determination of the operation date. Arteriography can now be reserved to those rare cases where digital angiography has failed; it can then be limited to the study of a specific territory, the site of puncture being located by digital angiography.

Adolescent↗
PubMed1986

Effect of human chorionic gonadotropin on luteinizing hormone and prolactin binding by testes of bilaterally cryptorchid rats.

This study investigates the ability of the testis in the cryptorchid state to bind luteinizing hormone (LH) and prolactin (Prl). For this purpose, rats were made bilaterally cryptorchid at 21 days of age; sham-operated rats were used as controls. At 56 days, the animals were injected with saline or with increasing doses of human chorionic gonadotropin (hCG: 1, 10 or 100 IU) and killed 8 or 24 h after injection. Cryptorchidism and injection of hCG did not alter plasma Prl levels. In cryptorchid rats, both LH and Prl binding expressed in pmol/testis were lower than in sham-operated controls (about 75% and 65%, respectively), but unchanged (LH binding) or increased (Prl binding) when expressed in pmol/g testis. In controls, 100 IU hCG induced a significant decrease in LH binding at 24 h. Prl binding was also significantly lower in controls injected with 100 IU hCG than in those injected with 1 or 10 IU hCG, at 8 h. In cryptorchid rats injected with 100 IU hCG, the LH binding fell 8 h and 24 h after injection; at 24 h, hCG reduced Prl binding. In conclusion, there was a considerable decrease in LH and Prl receptors in the abdominal testes. The negative regulation of these receptors in response to hCG was maintained, but at times and for doses which differed from those observed in scrotal testes.

Animals↗