Progressive methylation of POU5F1 regulatory regions during blastocyst development.

The POU5F1 gene encodes one of the 'core' transcription factors necessary to establish and maintain pluripotency in mammals. Its function depends on its precise level of expression, so its transcription has to be tightly regulated. To date, few conserved functional elements have been identified in its 5' regulatory region: a distal and a proximal enhancer, and a minimal promoter, epigenetic modifications of which interfere with POU5F1 expression and function in in vitro-derived cell lines. Also, its permanent inactivation in differentiated cells depends on de novo methylation of its promoter. However, little is known about the epigenetic regulation of POU5F1 expression in the embryo itself. We used the rabbit blastocyst as a model to analyze the methylation dynamics of the POU5F1 5' upstream region, relative to its regulated expression in different compartments of the blastocyst over a 2-day period of development. We evidenced progressive methylation of the 5' regulatory region and the first exon accompanying differentiation and the gradual repression of POU5F1 Methylation started in the early trophectoderm before complete transcriptional inactivation. Interestingly, the distal enhancer, which is known to be active in naïve pluripotent cells only, retained a very low level of methylation in primed pluripotent epiblasts and remained less methylated in differentiated compartments than the proximal enhancer. This detailed study identified CpGs with the greatest variations in methylation, as well as groups of CpGs showing a highly correlated behavior, during differentiation. Moreover, our findings evidenced few CpGs with very specific behavior during this period of development.

Different co-culture systems have the same impact on bovine embryo transcriptome.

During the last few years, several co-culture systems using either BOEC or VERO feeder cells have been developed to improve bovine embryo development and these systems give better results at high oxygen concentration (20%). In parallel, the SOF medium, used at 5% O2, has been developed to mimic the oviduct fluid. Since 2010s, the SOF medium has become popular in improving bovine embryo development and authors have started to associate this medium to co-culture systems. Nevertheless, little is known about the putative benefit of this association on early development. To address this question, we have compared embryo transcriptomes in four different culture conditions: SOF with BOEC or VERO at 20% O2, and SOF without feeders at 5% or 20% O2 Embryos have been analyzed at 16-cell and blastocyst stages. Co-culture systems did not improve the developmental rate when compared to 5% O2 Direct comparison of the two co-culture systems failed to highlight major differences in embryo transcriptome at both developmental stages. Both feeder cell types appear to regulate the same cytokines and growth factors pathways, and thus to influence embryo physiology in the same way. In blastocysts, when compared to culture in SOF at 5% O2, BOEC or VERO seems to reduce cell survival and differentiation by, at least, negatively regulating STAT3 and STAT5 pathways. Collectively, in SOF medium both blastocysts rate and embryo transcriptome suggest no influence of feeder origin on bovine early development and no beneficial impact of co-culture systems when compared to 5% O2.

Growth and Yield Responses of Cowpea to Inoculation and Phosphorus Fertilization in Different Environments.

Cowpea (Vigna unguiculata) is a major source of dietary protein and essential component of the cropping systems in semi-arid regions of Sub-Saharan Africa. However, yields are very low due to lack of improved cultivars, poor management practices, and limited inputs use. The objectives of this study were to assess the effects of rhizobia inoculant and P on nodulation, N accumulation and yield of two cowpea cultivars in Mozambique. Field study was conducted in three contrasting environments during the 2013/2014 and 2014/2015 seasons using randomized complete block design with four replications and four treatments. Treatments consisted of seed inoculation, application of 40 kg P2O5 ha-1, inoculation + P, and a non-inoculated control. The most probable number (MPN) technique was used to estimate the indigenous bradyrhizobia populations at the experimental sites. The rhizobia numbers at the sites varied from 5.27 × 102 to 1.07 × 103 cells g-1 soil. Inoculation increased nodule number by 34-76% and doubled nodule dry weight (78 to 160 mg plant-1). P application improved nodulation and interacted positively with the inoculant. Inoculation, P, and inoculant + P increased shoot dry weight, and shoot and grain N content across locations but increases in number of pods plant-1, seeds pod-1, and 100-seed weight were not consistent among treatments across locations. Shoot N content was consistently high for the inoculated plants and also for the inoculated + P fertilized plants, whereas the non-inoculated control plants had the lowest tissue N content. P uptake in shoot ranged from 1.72 to 3.77 g kg-1 and was higher for plants that received P fertilizer alone. Inoculation and P either alone or in combination consistently increased cowpea grain yield across locations with yields ranging from 1097 kg ha-1 for the non-inoculated control to 1674 kg ha-1 for the inoculant + P treatment. Grain protein concentration followed a similar trend as grain yield and ranged from 223 to 252 g kg-1 but a negative correlation between grain yield and protein concentration was observed. Inoculation increased net returns by $104-163 ha-1 over that for the control. The results demonstrate the potential of improving cowpea grain yield, quality and profitability using inoculant, although the cost-benefit for using P at the current fertilizer price is not attractive except when applied together with inoculant at low P site.

[Morphometric study of the lumbosacral plexus innervating the muscles of the rat pelvic floor]. / Etude morphométrique des noyaux lombo-sacrés innervant les muscles du plancher pelvien chez le rat.

Motoneurons of the pelvic muscles in the lumbo-sacral segment of the spinal cord have been extensively studied in different species. However, few informations occur in the literature about the individual morphology of each group of neurons and their connections. Thus, in the Rat we have studied the neuronal mapping of 5 pelvic muscles, bulbospongiosus, ischio-cavernosus, levator ani, sphincter ani, sphincter urethrae, using a retrograde tracer, the horseradish peroxidase (H.R.P.). Most of the muscles injected by H.R.P. receive their innervation from the motoneurons located in the homolateral side of the spinal cord. The motoneurons of sphincter ani (+/- 40) and those of the bulbo-spongiosus (+/- 50) have the same morphology. Their dendrites contact contralateral motoneurons. They are situated in the dorso-medial nucleus of the L5-L6 segments of the spinal cord. The motoneurons of the ischio-cavernosus (+/- 80) and those of sphincter urethrae (+/- 40) are situated in the dorsolateral nucleus of the L5-S1 segments of the spinal cord where they form two distinct groups. On the contrary, in the ventro-medial nucleus, the neurons are mixed. The dendrites in the dorso-lateral nucleus form an important longitudinal network. The motoneurons of the levator ani (+/- 50) are situated in the ventral nucleus of the L5-S1 segments. Our works demonstrate the significance of the dendritic networks: they could play a role in the synchronization and the activity of the pelvic muscles.(ABSTRACT TRUNCATED AT 250 WORDS)

[Morphometry of sacral neurons innervating the pelvic muscles. Experimental study]. / Morphométrie des noyaux sacrés innervant les muscles pelviens. Etude expérimentale.

Sacral motoneurons of the pelvic muscles have been extensively studied in the rat (1,2). Few informations occur in the literature on their specific morphology and their interconnection. In an experimental study we have differentiated the neuronal mapping of the: bulbo-spongiosus (B.S.M.), ischio-cavernosus (I.C.M.), levator ani (L.A.M.), sphincter ani (S.A.M.) and sphincter urethrae (S.U.M.) muscles. Each different or both sided pelvic muscle of 30 wistar rats have been injected by a solution of horse-radish-peroxidase. Using this H.R.P. technique, the mapping of the marked neurons and compared to the different muscles has been performed on horizontal and transversal spinal cord sections. A statistical study using the "T" test compares the maximal and minimal diameters and the surface of the neurons. 1. Most of the muscles injected in one side left or right receive their innervation from the neurons located in the homolateral side of the spinal cord. 2. The B.S.M. and the S.A.M. receive, in part, an innervation from the opposite side. 3. The neurons of the B.S.M. and of the S.A.M. are located in the D.M. group of L5 - L6 segment of the spinal cord. Their diameters are significantly different but not their surfaces (+/- 940 mu 2). 4. The neurons of the I.C.M. and of the S.U.M. located in the D.L. group have an equivalent diameter and surface. 5. The neurons of the L.A.M. have the largest diameter but an equivalent surface to the others. This work on a mammalian model brings further informations on the mapping of the sacral innervation of the pelvic muscles and offers a comparative reference for Man.

[Ultrastructural modifications of the bladder wall in senescence]. / Modifications ultrastructurales de la paroi vésicale au cours de la sénescence.

Histochemical and ultrastructural studies of the epithelial, muscular, connective, vascular and nervous tissue layers have been carried on endoscopic or surgical biopsies in patients from 23 to 92 years old. Beyond 70 years old, the junctional complexes between the superficial cells of the epithelium are altered and the number of intracellular organelles is diminished. The intercellular spaces and binds between the muscle cells are modified. Some interstitial fibrosis occurs and the density of the connective tissue increases. The authors describe also similar observation in the bladder wall of the old rats. An arteriosclerosis of small vessels is observed. The density of the autonomous nervous network is reduced and the cholinergic innervation becomes preponderant. No specific ultrastructural modification of the nerves is seen except a neuromuscular infiltration by a conjunctive hyperplastic tissue. These morphological changes can be related to some modifications of the vesical compliance.

[Levator muscles pf the anus (levator ani). Normal or pathological cytoarchitecture of endorectal biopsies in man]. / Muscles releveurs de l'anus (levator ani) cytoarchitecture normale ou pathologique prélèvements endorectaux chez l'homme.

The structure and ultrastructure of normal or pathological needle biopsies of the human levator ani are studied. Disturbances of the muscular cyto-architecture: cellular degeneration with infiltration of glycogen and disorganization of the myofibrillar A, I and Z stripes are shown. The comparison between the histological data and the clinical results demonstrates that the quality of the levator ani is not always clearly defined by the clinic. The muscular biopsy reaches its main interest when in physical reeducation or in surgical correction of the incontinence, some doubt remains on the clinical value of the levator ani.

[Changes in intrinsic autonomic innervation in congenital or primary megabladder]. / Altérations de l'innervation neurovégétative intrinsèque dans les mégavessies congénitales ou primaires.

In eleven non-diabetic women suffering from high compliance bladder, the authors correlate urodynamic findings with the modifications of the autonomic vesical innervation. Endoscopic biopsies show a dramatic reduction in acetylcholinesterase-positive innervation in the detrusor but less visible in the trigone. The adrenergic network density is also reduced in both areas, according to age. Congenital conditions, high pressure mechanisms, vascular hypoxia explain these autonomic alterations inducing iatrogenic problems associated with different drug treatments. In some cases, urethral hypertonic instability acts in the same way as mechanical obstruction.

[Evaluation of the density of acetylcholinesterase-positive and intrinsic adrenergic innervation of the uterus in rats]. / Evaluation de la densité de l'innervation acétylcholinestérase-positive et adrénergique intrinsèque de l'utérus chez le rat.

According to the Karnovsky and Roots modified by E1 Badawi and Schenk's technique for the acetylcholinesterase-positive innervation and according to the Lindvall and Björklund modified by de la Torre and Surgeon's method for the adrenergic one, we have demonstrated the nervous fibers in the different tissues of the cervix, the corpus and the cornu of the she-rat in pro-oestrus. A statistic evaluation of the density of these nervous networks has been established for the different regions. The study of the histograms demonstrates the predominance of acetylcholinesterase-positive innervation versus the adrenergic one. The evolution of the nervous densities is similar for each tissue in the corpus and the cornu, these of the myometrium are the highest. In the cervix, the acetylcholinesterase-positive fibers dominate over the mucosal and submucosal ones, on the other hand, the adrenergic ones are richest in the muscle. Our morphometric studies confirm statistically the optic observations of the others authors.

[Cholinergic and adrenergic innervation of the bladder obstructed by urethral stenosis in the rat]. / L'innervation cholinergique et adrénergique de la vessie obstruée par sténose de l'urètre chez le rat.

In the obstructed bladder by urethral stenosis the morphometry studies show a decrease of the cholinergic and adrenergic intrinsic innervation in a different way according the tissue layer and the experimental delay. Adrenergic nerves are more affected than cholinergic ones but they recover more quickly. In the adventitia and the sub-mucosa first affected by the high pressures inside the bladder the density of the autonomous nerves decreases from the first week. The perivascular and muscular nervous fibers are less sensitive and the similar shape of their innervation histogram gives evidence of a tight bond between their adrenergic network. Beside their motor participation the adrenergic terminal fibers may play a role in the cellular trophicity of the muscle.

[Modification of the tissue thickness of the bladder in obstruction by urethral stenosis]. / Modification des épaisseurs tissulaires de la vessie au cours de son obstruction par sténose urétrale.

In experimental obstructed bladder by urethral stenosis, the trigone and the detrusor walls thicken in a very important but different way. The thickened mucosa and submucosa of the total bladder show oedema and hypertrophy of the connective fibro-elastic tissue. Related to the different axis of the pressure inside the bladder and the specific muscular architecture of both regions, the adventitial and muscular layers show no modification in the trigone but they become thinner in the detrusor.

[Density of the neurovegetative innervation of the uterus of rats]. / Densité de l'innervation neurovégétative de l'utérus chez la ratte.

Using the Karnovsky and Roots modified by E1 Badawi and Schenk's technic for the cholinergic innervation and with the method of Lindvall and Björklund modified by de la Torre and Surgeon for the adrenergic ones, we demonstrate the innervation of each tissular layer, in cervix, corpus and cornua of the uterus of the she-rat in pro-oestrus state. A statistic evaluation is established for the different areas. The density of cholinergic innervation is richer than the adrenergic one. The number of cholinergic fibers is maximum in the cervix. It decreases in corpus and cornua especially in the mucosal and sub-mucosal layers. The density of the muscular nervous network is predominant in the corpus versus the cervix. The number of adrenergic nerves is maximum in corpus it diminishes in the cervix and the cornua. In each region, the muscular adrenergic network domines over the other tissular layers. We confirm statistically morphometric non parametric observations of these other authors.