Improvement of the guiding performances of near infrared organic/inorganic channel waveguides

New sol-gel derived organic/inorganic hybrid single mode waveguides devices have been developed for telecommunication applications in the two near infrared windows at 1310 and 1550 nm. The overall procedure of fabrication of these devices is described and the refractive indices of the guiding, the buffer and the protective layers are adjusted by a precise control of the materials' composition. Due to the improvement of the composition of the guiding layer, the attenuation losses are significantly decreased to 0.8 dB/cm and 2dB/cm at respectively 1310 and 1550 nm

TOWARDS A DATA MODEL FOR PLM APPLICATION IN BIO-MEDICAL IMAGING

International audienceBio-Medical Imaging (BMI) is currently confronted to data issues similar to those of the manufacturing industry twenty years ago. In particular, the need for data sharing and reuse has never been so strong to foster major discoveries in neuroimaging. Some data management systems have been developed to meet the requirements of BMI large-scale research studies. However, many efforts to integrate the data provenance along a research study, from the specifications to the published results, are to be done. Product Lifecycle Management (PLM) systems are designed to comply with manufacturing industry expectations of providing the right information at the right time and in the right context. Consequently PLM systems are proposed to be relevant for the management of BMI data. From a need analysis led with the GIN research group, the BMI-LM data model is designed: it is PLM-oriented, generic (enabling the management of many types of data such as imaging, clinical, psychology or genetics), flexible (enabling users’ customisation) and it covers the whole stages of a BMI study from specifications to publication. The test implementation of the BMI-LM model into a PLM system is detailed. The preliminary feed-back of the GIN researchers is discussed in this paper: the BMI-LM data model and the PLM concepts are relevant to manage BMI data, but PLM systems interfaces are unsuitable for BMI researchers

Mammary cell activity and turnover in dairy cows treated with the prolactin-release inhibitor quinagolide and milked once daily

To assess the regulation of mammary cell activity, survival, and proliferation by prolactin (PRL), 5 Holstein cows in early lactation received daily i.m. injections of 1 mg of quinagolide, a suppressor of PRL release, for 9 wk, whereas 4 control cows received the vehicle (water) only. During the last week of treatment, one udder half was milked once a day (1×) and the other twice a day (2×). Mammary biopsies were harvested 1 wk before and 4 and 8 wk after the start of quinagolide treatment. The quinagolide injections reduced milk yield and resulted in lower levels of κ-casein and α-lactalbumin mRNA in the mammary biopsies at wk 4 compared with the control cows. In the mammary tissue of the quinagolide-treated cows at wk 8 of treatment, cell proliferation (as determined by proliferating cell nuclear antigen labeling) was lower and apoptosis (as determined by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay) was higher than in the mammary tissue of the control cows. During differential milking, mammary epithelial cells (MEC) were extracted from the milk by centrifugation and purified by immunocytochemical binding to allow variations in the levels of mammary transcripts to be observed. After 9 wk of treatment, levels of α-lactalbumin and κ-casein mRNA were lower in the MEC isolated from milk of the quinagolide-treated cows. This effect was associated with lower PRL receptor mRNA levels and a tendency toward lower viability in the milk-isolated MEC from the 2×-milked glands. The decrease from 2× milking to 1× milking also downregulated α-lactalbumin and κ-casein transcripts in the milk-isolated MEC. Viability was higher for the MEC collected from the 1×-milked udder halves compared with the 2×-milked halves. In conclusion, the reduction in milk yield after chronic administration of the PRL-release inhibitor quinagolide is associated with a reduction in mammary cell activity, survival, and proliferation in lactating dairy cows. Reduced milking frequency was also associated with a decrease in MEC activity

Comparison of five different RNA sources to examine the lactating bovine mammary gland transcriptome using RNA-Sequencing.

The objective of this study was to examine five different sources of RNA, namely mammary gland tissue (MGT), milk somatic cells (SC), laser microdissected mammary epithelial cells (LCMEC), milk fat globules (MFG) and antibody-captured milk mammary epithelial cells (mMEC) to analyze the bovine mammary gland transcriptome using RNA-Sequencing. Our results provide a comparison between different sampling methods (invasive and non-invasive) to define the transcriptome of mammary gland tissue and milk cells. This information will be of value to investigators in choosing the most appropriate sampling method for different research applications to study specific physiological states during lactation. One of the simplest procedures to study the transcriptome associated with milk appears to be the isolation of total RNA directly from SC or MFG released into milk during lactation. Our results indicate that the SC and MFG transcriptome are representative of MGT and LCMEC and can be used as effective and alternative samples to study mammary gland expression without the need to perform a tissue biopsy

Insulin-like growth factor binding proteins initiate cell death and extracellular matrix remodeling in the mammary gland

We have demonstrated that insulin-like growth factor binding protein-5 (IGFBP-5) production by mammary epithelial cells increases dramatically during forced involution of the mammary gland in rats, mice and pigs. We proposed that growth hormone (GH) increases the survival factor IGF-I, whilst prolactin (PRL) enhances the effects of GH by decreasing the concentration of IGFBP-5, which would otherwise inhibit the actions of IGFs. To demonstrate a causal relationship between IGFBP-5 and cell death, we created transgenic mice expressing IGFBP-5, specifically, in the mammary gland. DNA content in the mammary glands of transgenic mice was decreased as early as day 10 of pregnancy. Mammary cell number and milk synthesis were both decreased by approximately 50% during the first 10 days of lactation. The concentrations of the pro-apoptotic molecule caspase-3 was increased in transgenic animals whilst the concentrations of two pro-survival molecules Bcl-2 and Bcl-x were both decreased. In order to examine whether IGFBP-5 acts by inhibiting the survival effect of IGF-I, we examined IGF receptor- and Akt-phoshorylation and showed that both were inhibited. These studies also indicated that the effects of IGFBP-5 could be mediated in part by IGF-independent effects involving potential interactions with components of the extracellular matrix involved in tissue remodeling, such as components of the plasminogen system, and the matrix metallo-proteinases (MMPs). Mammary development was normalised in transgenic mice by R3-IGF-I, an analogue of IGF-I which binds weakly to IGFBPs, although milk production was only partially restored. In contrast, treatment with prolactin was able to inhibit early involutionary processes in normal mice but was unable to prevent this in mice over-expressing IGFBP-5, although it was able to inhibit activation of MMPs. Thus, IGFBP-5 can simultaneously inhibit IGF action and activate the plasminogen system thereby coordinating cell death and tissue remodeling processes. The ability to separate these properties, using mutant IGFBPs, is currently under investigatio

Cabergoline treatment at dry-off facilitated the remodelling and the lactoferrin immunoprotection of the mammary tissue in dairy cows

ObjectivesIn ruminants, the early phase of drying-off is a period of intense mammary gland involution that is due, in part, to dramatic decline prolactin (PRL) release. The speed at which the bovine mammary gland involutes following the abrupt cessation of lactation is also directly related to the risk of new intramammary infections. Thus, strategies to hasten involution following dry-off could have implications in preventing mastitis and optimizing mammary tissue regenerative processes.Materials and methodsTo assess the effect of prolactin inhibition by cabergoline on mammary gland involution, 14 Holstein dairy cows were injected with a single i.m. administration of 5.6 mg cabergoline (n=7) or placebo (n=7) within 4 hours after the last milking before the drying off at the day of drying-off (D0). Mammary secretion samples were collected using a teat-cannula once during lactation (D-6) and at D1, D2, D3, D4, D8 and D14 after the drying-off. The mammary secretion samples were used for lactoferrin and zymography analyses to detect the activity of enzymes such as MMP, matrix metalloproteinases involved in the remodelling of mammary tissue during involution. Mammary epithelial cells (MEC) were also purified from mammary secretions after centrifugation andimmunocytochemical binding in order to evaluate the MEC exfoliation. Mammary biopsy samples were collected one week before drying-off (D-6), at D1 and at D8 and used for lactoferrin immunochemistry and zymography analyses.ResultsThe activity of MMP9 increased after drying-off in mammary secretions (P < 0.001). Cabergoline increased the activity of MMP9 (1.7 fold, P < 0.05) in mammary secretions and MMP-2 in mammary tissue after drying-off (1.4 fold, P ≤ 0.01). MEC concentration progressively increased in mammary secretions after drying-off (P < 0.01). Cabergoline induced an increase in MEC concentration (P =0.04). Lactoferrin content progressively increased in mammary secretions during involution. The rise of lactoferrin content in mammary secretions was significant starting at D4 in the cabergoline treated cows (P ≤0.05) whereas it only happened at D8 in controls (P < 0.05). Overall, cabergoline treatment increased lactoferrin content of mammary secretions (P = 0.10). The total lactoferrin immunostaining in the mammary tissue increased after drying-off (P < 0.05). Compared with during lactation, this increase was observed at D1 and D8, respectively for cabergoline treated cows and control cows (P <0.05).ConclusionsOur results indicate that cabergoline treatment was efficient to enhance the extracellular matrix mammary remodeling, and the MEC exfoliation from the mammary epithelium and also hasten the udder immunoprotection by lactoferrin and therefore facilitates the drying-off

In Vivo Inhibition Followed by Exogenous Supplementation Demonstrates Galactopoietic Effects of Prolactin on Mammary Tissue and Milk Production in Dairy Cows

ABSTRACT: It has been previously shown that the long-term inhibition of milking-induced prolactin (PRL) release by quinagolide (QN), a dopamine agonist, reduces milk yield in dairy cows. To further demonstrate that PRL is galactopoietic in cows, we performed a short-term experiment that used PRL injections to restore the release of PRL at milking in QN-treated cows. Nine Holstein cows were assigned to treatments during three 5-d periods in a 3 × 3 Latin square design: 1) QN: twice-daily i.m. injections of 1 mg of QN; 2) QN-PRL: twice-daily i.m. injections of 1 mg of QN and twice-daily (at milking time) i.v. injections of PRL (2 μg/kg body weight); and 3) control: twice-daily injections of the vehicles. Mammary epithelial cells (MEC) were purified from milk so that their viability could be assessed, and mammary biopsies were harvested for immunohistological analyses of cell proliferation using PCNA and STAT5 staining. In both milk-purified MEC and mammary tissue, the mRNA levels of milk proteins and BAX were determined using real-time reverse-transcription PCR. Daily QN injections reduced milking-induced PRL release. The area under the PRL curve was similar in the control and PRL injection treatments, but the shape was different. The QN treatment decreased milk, lactose, protein, and casein production. Injections of PRL did not restore milk yield but tended to increase milk protein yield. In mammary tissue, the percentage of STAT5-positive cells was reduced during QN but not during QN-PRL in comparison with the control treatment. The percentage of PCNA-positive cells was greater during QN-PRL injections than during the control or QN treatment and tended to be lower during QN than during the control treatment. In milk-purified MEC, κ-casein and α-lactalbumin mRNA levels were lower during QN than during the control treatment, but during QN-PRL, they were not different from the control treatment. In mammary tissue, the BAX mRNA level was lower during QN-PRL than during QN. The number of MEC exfoliated into milk was increased by QN injections but tended to be decreased by PRL injections. Injections of PRL also increased the viability of MEC harvested from milk. Although PRL injections at milking could not reverse the effect of QN treatment on milk production, their effects on cell survival and exfoliation and on gene expression suggest that the effect of QN treatment on the mammary gland is due to QN’s inhibition of PRL secretion

Cabergoline treatment at dry-off accelerated mammary involution as indicated by mammary secretion composition changes in dairy cows

In ruminants, the early phase of drying-off is a period of mammary gland involution that is marked by the cessation of prolactin (PRL) release. The speed at which the bovine mammary gland involutes following the abrupt cessation of lactation is directly related to the risk of new intramammary infections.ObjectivesOur aim was to assess the effect of PRL inhibition by cabergoline on the speed of the mammary gland involution, through analysis of the changes of mammary secretion composition.Materials and methodsFourteen Holstein dairy cows were injected with a single i.m. administration of 5.6 mg cabergoline (n=7) (Velactis ®, Ceva Sante Animale) or placebo (n=7) at the first day of dryingoff (D0). Mammary secretion samples were collected using a teat-cannula once during lactation (D-6) and at D1, D2, D3, D4, D8 and D14 after the drying-off. The mammary secretion samples were used for milk fat, lactose, true protein, alpha-lactalbumin and SCC analysis. Mammary biopsy samples were collected one week before drying-off (D-6), at D1 and at D8 and used for RNA extraction and RT-PCR analyses.ResultsAs expected, SCC progressively increased whereas lactose content decreased in mammary secretions after drying-off (P < 0.001). The increase in SCC was 2.4 fold higher in cabergoline treated cows than in control cows (P < 0.01). The decrease of lactose content in mammary secretions progressively decreased during involution and was associated with paralleled change in GLUT-1 mRNA level coding the main glucose transporter in the udder. These decreases were faster in cabergoline treated cows compared to controls with lower lactose content in cabergoline treated cows already by D1 than in controls (P < 0.05) and significant decrease in GLUT-1 mRNA levels at D1 and D8 respectively for cabergoline and control treatments compared to D-6 (P ≤ 0.05). Cabergoline treatment tended to increase fat content at D3 after drying-off (P < 0.10). No significant effects of cabergoline treatment were observed both in true protein and in alpha-lactalbumin contents in mammary secretions or in alphalactalbumin and kappa-casein mRNA levels in mammary tissues.ConclusionsThe changes in lactose, SCC and fat in mammary secretions and GLUT-1 mRNA level in the udder, indicate that cabergoline treatment was efficient to hasten the mammary gland involution without affecting milk protein synthesis in the mammary tissue. Cabergoline could facilitate dairy management at the time of dry-off