In Vitro and In Vivo Efficiency of Extenders Added to Thawed Stallion Semen.

BACKGROUND: Addition of extenders to thawed semen could improve fertility. OBJECTIVE: To determine the efficiency of extenders to increase viability of thawed semen, measured by sperm parameters in vitro and pregnancy rates after artificial insemination (AI). MATERIALS AND METHODS: Sperm motility and acrosin activity were measured during a thermoresistance test (TRT). RESULTS: Progressive motility decreased (P<0.05) after 30 min in thawing semen treated with saline solution (SS) and only after 60 min with Tyrode's solution (TS) or freezing diluent (FD). The total motility decreased (P<0.05) after 60 min in thawed semen treated with SS, and after 90 min in thawed semen containing TS or FD. The acrosin activity decreased (P<0.05) after 60 min during the TRT, but there was no difference among treatments throughout the TRT. The pregnancy rates were similar among thawed-semen supplemented with SS, TS or FD. CONCLUSION: The extenders neither improve sperm parameters nor enhance AI results.

Freezing of Stallion Semen: in vitro and in vivo Evaluation of Sperm Motility and Acrosin Activity in Frozen-thawed Semen with Addition of Post-diluent Extenders.

BACKGROUND: Post-diluents could potentially increase semen cryotolerance, but remain poorly explored in horses. OBJECTIVE: The aim was to evaluate the efficiency of post-diluents on frozen-thawed semen viability of two stallions (S1-S2). MATERIALS AND METHODS: The cryopreserved semen was thawed at 50°C for 40 seconds. Semen motility and acrosin activity (AA) were determined during the thermo-resistance test (TRT). RESULTS: Progressive motility of S2 semen decreased after 60 and 90 minutes of TRT (TRT60 and TRT90) on the control compared to both post-diluents. The total motility of both S1 and S2 decreased on TRT60 and TRT90 semen control versus both Ringer and Merk post-diluents. The AA on S1 was higher than S2 throughout the TRT. Pregnancy rates after artificial insemination (AI) were similar among post-diluents and stallions. CONCLUSION: Post-diluents do not contribute to predicting frozen-thawed semen fertility or the efficiency of equine AI.

SNPs at miR-155 binding sites of TYRP1 explain discrepancy between mRNA and protein and refine TYRP1 prognostic value in melanoma.

BACKGROUND: We previously demonstrated an inverse correlation between tyrosinase-related protein 1 (TYRP1) mRNA expression in melanoma metastases and patient survival. However, TYRP1 protein was not detected in half of tissues expressing mRNA and did not correlate with survival. Based on a study reporting that 3' untranslated region (UTR) of TYRP1 mRNA contains two miR-155-5p (named miR-155) binding sites exhibiting single-nucleotide polymorphisms (SNPs) that promote (matched miRNA-mRNA interaction) mRNA decay or not (mismatched), we aimed to investigate the role of miR-155 in the regulation of TYRP1 mRNA expression and protein translation accounting for these SNPs. METHODS: The effect of miR-155 on TYRP1 mRNA/protein expression was evaluated in two melanoma cell lines harbouring matched or mismatched miR-155-TYRP1 mRNA interaction after transfection with pre-miR-155. In parallel, 192 skin and lymph node melanoma metastases were examined for TYRP1 mRNA/protein, miR-155 and SNPs and correlated with patient survival. TYRP1 mRNA, SNPs at its 3'UTR and miR-155 were analysed by RT-qPCR, whereas TYRP1 protein was evaluated by western blot in cell lines and by immunohistochemistry in metastatic tissues. RESULTS: The miR-155 induced a dose-dependent TYRP1 mRNA decay and hampered its translation into protein in the line with the 'match' genotype. In melanoma metastases, TYRP1 mRNA inversely correlated with miR-155 expression but not with TYRP1 protein in the 'match' group, whereas it positively correlated with protein but not with miR-155 in the 'mismatch' group. Consequently, in the latter group, TYRP1 protein inversely correlated with survival. CONCLUSION: Polymorphisms in 3'UTR of TYRP1 mRNA can affect TYRP1 mRNA regulation by miR-155 and its subsequent translation into protein. These SNPs can render TYRP1 mRNA and protein expression nonsusceptible to miR-155 activity and disclose a prognostic value for TYRP1 protein in a subgroup of melanoma patients. These data support the interest in the prognostic value of melanogenic markers and propose TYRP1 to refine prognosis in patients with advanced disease.

Vibrational Spectroscopy and Phonon-Related Properties of the L-Aspartic Acid Anhydrous Monoclinic Crystal.

The infrared absorption and Raman scattering spectra of the monoclinic P21 l-aspartic acid anhydrous crystal were recorded and interpreted with the help of density functional theory (DFT) calculations. The effect of dispersive forces was taken into account, and the optimized unit cells allowed us to obtain the vibrational normal modes. The computed data exhibits good agreement with the measurements for low wavenumbers, allowing for a very good assignment of the infrared and Raman spectral features. The vibrational spectra of the two lowest energy conformers of the l-aspartic molecule were also evaluated using the hybrid B3LYP functional for the sake of comparison, showing that the molecular calculations give a limited description of the measured IR and Raman spectra of the l-aspartic acid crystal for wavenumbers below 1000 cm(-1). The results obtained reinforce the need to use solid-state calculations to describe the vibrational properties of molecular crystals instead of calculations for a single isolated molecule picture even for wavenumbers beyond the range usually associated with lattice modes (200 cm(-1) < ω < 1000 cm(-1)).

L-Asparagine crystals with wide gap semiconductor features: optical absorption measurements and density functional theory computations.

Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences Δa, Δb, Δc between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z → Γ and Z → ß transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3 → Γ, α1 → Γ, and α2 → Γ transitions, respectively. Δ-sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p-carboxyl, C 2p-side chain, and C 2p-carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree of optical anisotropy for the absorption and complex dielectric function, with more structured curves for incident light polarized along the 100 and 101 directions.

Tyrosinase-related protein 1 mRNA expression in lymph node metastases predicts overall survival in high-risk melanoma patients.

BACKGROUND: Clinical outcome of high-risk melanoma patients is not reliably predicted from histopathological analyses of primary tumours and is often adjusted during disease progression. Our study aimed at extending our previous findings in skin metastases to evaluate the prognostic value of tyrosinase-related protein 1 (TYRP1) in lymph node metastases of stages III and IV melanoma patients. METHODS: TYRP1 mRNA expression in 104 lymph node metastases was quantified by real-time PCR and normalised to S100 calcium-binding protein B (S100B) mRNA expression to correct for tumour load. TYRP1/S100B ratios were calculated and median was used as cutoff value. TYRP1/S100B mRNA values were correlated to clinical follow-up and histopathological characteristics of the primary lesion. RESULTS: A high TYRP1/S100B mRNA ratio significantly correlated with reduced disease-free (DFS) and overall survival (OS; Cox regression analysis, P=0.005 and 0.01, respectively), increased Breslow thickness (Spearman's rho test, P<0.001) and the presence of ulceration (Mann-Whitney test, P=0.02) of the primaries. Moreover, high TYRP1/S100B was of better prognostic value (lower P-value) for OS than Breslow thickness and ulceration. Finally, it was well conserved during disease progression with respect to high/low TYRP1 groups. CONCLUSION: High TYRP1/S100B mRNA expression in lymph node metastases from melanoma patients is associated with unfavourable clinical outcome. Its evaluation in lymph node metastases may refine initial prognosis for metastatic patients, may define prognosis for those with unknown or non-evaluable primary lesions and may allow different management of the two groups of patients.

Essential oil of Juniperus communis subsp. alpina (Suter) Celak needles: chemical composition, antifungal activity and cytotoxicity.

Essential oils are known to possess antimicrobial activity against a wide spectrum of bacteria and fungi. In the present work the composition and the antifungal activity of the oils of Juniperus communis subsp. alpina (Suter) Celak were evaluated. Moreover, the skin cytotoxicity, at concentrations showing significant antifungal activity, was also evaluated. The oils were isolated by hydrodistillation and analysed by gas chromatography and gas chromatography-mass spectrometry. Minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oil against dermatophytes (Epidermophyton floccosum, Microsporum canis, M. gypseum, Trichophyton mentagrophytes, T. mentagrophytes var. interdigitale, T. rubrum, T. verrucosum), yeasts (Candida albicans, C. guillermondii, C. krusei, C. parapsilosis, C. tropicalis, Cryptococcus neoformans) and Aspergillus species (Aspergillus flavus, A. fumigatus, A. niger). Cytotoxicity was tested in HaCaT keratinocytes through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Essential oil of J. communis subsp. alpina needles was predominantly composed of monoterpene hydrocarbons (78.4%), with the main compounds being sabinene (26.2%), α-pinene (12-9%) and limonene (10.4%). Results concerning the antifungal activity demonstrated the potential of needle oil against dermatophytes, particularly for Microsporum canis and Trichophyton rubrum with MIC and MLC of 0.32 µL/mL. Furthermore, evaluation of cell viability showed no significant cytotoxicity in HaCaT keratinocytes at concentrations between 0.32 and 0.64 µL/mL. These results show that it is possible to find appropriate doses of J. communis subsp. alpina oil with both antifungal activity and a very low detrimental effect on keratinocytes.

[Survey concerning exposure of staff to UV radiation at four Brussels hospitals]. / Enquête sur l'exposition aux rayons ultraviolets parmi le personnel de quatre hôpitaux bruxellois.

BACKGROUND: The incidence of melanoma has been increasing for 50 years. Exposure to ultraviolet (UV) radiation constitutes the main risk factor. The aim of this study was to analyze the impact on hospital staff behaviour with regard to UV of screening campaigns initiated in Belgium 11 years ago. PATIENTS AND METHODS: We performed a multicentre, before-after study by sending an anonymous survey to the staff of four hospital in Brussels, from March 2010 to April 2010 (group 2: n=895). Demographic, clinical and behavioural data were collected and compared to those collected 23 years ago in the same hospitals (group 1: n=2410). RESULTS: Phototypes in both groups were similar. In group 2, the distribution of naevi tended to be spread over the whole body and the severity of sunburn had decreased. Group 2 participants reported a reduction in active sun exposure, especially in the past 10 years, with less leisure-time tanning. There was a significant increase in holidays in sunny locations, although vacation time was shorter, with prolonged daily and annual exposure. Sunscreens were more frequently used and there was an increase in sun-bed use, especially in beauty parlours. CONCLUSION: Our study comprises a double snapshot of a population of hospital workers at an interval of 23 years. The information and screening campaigns do not seem to have had the desired effect on the hospital staff surveyed. Sunscreen use has in fact resulted in extended UV exposure and the observed exposure pattern is that most frequently involved in melanoma development.

TYRP1 mRNA expression in melanoma metastases correlates with clinical outcome.

BACKGROUND: Clinical outcome of patients with high-risk melanoma cannot be reliably predicted on the basis of classical histopathological examination. Our study aimed to determine in melanoma metastases a gene expression profile associated with patient survival, and to identify and validate marker(s) of poor clinical outcome. METHODS: Skin and lymph node metastases from melanoma patients (training population) were used to identify candidate prognostic marker(s) based on DNA microarray analysis. Additional skin metastases (validation population) were used to assess the prognostic value of the first ranked gene by real-time PCR. RESULTS: We performed microarray analysis in the training population and generated a list of 278 probe sets associated with a shorter survival. We used the first ranked gene, tyrosinase-related protein 1 (TYRP1), further measured its expression in the validation population by real-time PCR and found it to be significantly correlated with distant metastasis-free survival (DMFS), overall survival (OS) and Breslow thickness. We also found that it was fairly well conserved in the course of the disease regardless of the delay to metastasis occurrence. Finally, although Tyrp1 protein (immunohistochemistry (IHC)) was only detected in about half of the samples, we showed that its expression also correlated with Breslow thickness. CONCLUSION: Our data indicate that TYRP1 mRNA expression level, at least in skin metastases, is a prognostic marker for melanoma, and is particularly useful when prognostic pathology parameters at the primary lesion are lacking. Its conserved expression further supports its use as a target for therapy.

Anhydrous crystals of DNA bases are wide gap semiconductors.

We present the structural, electronic, and optical properties of anhydrous crystals of DNA nucleobases (guanine, adenine, cytosine, and thymine) found after DFT (Density Functional Theory) calculations within the local density approximation, as well as experimental measurements of optical absorption for powders of these crystals. Guanine and cytosine (adenine and thymine) anhydrous crystals are predicted from the DFT simulations to be direct (indirect) band gap semiconductors, with values 2.68 eV and 3.30 eV (2.83 eV and 3.22 eV), respectively, while the experimentally estimated band gaps we have measured are 3.83 eV and 3.84 eV (3.89 eV and 4.07 eV), in the same order. The electronic effective masses we have obtained at band extremes show that, at low temperatures, these crystals behave like wide gap semiconductors for electrons moving along the nucleobases stacking direction, while the hole transport are somewhat limited. Lastly, the calculated electronic dielectric functions of DNA nucleobases crystals in the parallel and perpendicular directions to the stacking planes exhibit a high degree of anisotropy (except cytosine), in agreement with published experimental results.

Carrier transport investigation in short-wavelength InAs/AlGaAs quantum dots.

Spatially resolved photoluminescence has been used to investigate the details of the carrier capture and recombination dynamics in InAs/AlGaAs self-assembled quantum dots. The spatial PL distribution displays a Gaussian-like profile, whose width depends upon the temperature and detection energy being analyzed. The results give evidence of carrier thermalization between dots with different sizes. The effects of carrier transport in the quantum dot (QD) structure and carrier capture cannot be separated. The results can be modeled by assuming a carrier hopping process.

Combined Application of Entomopathogenic Nematodes and Insecticides in the Control of Leaf-Miner Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) on Tomato.

The present research aimed to investigate the compatibility of entomopathogenic nematodes (EPNs) and registered insecticides for the control of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in the tomato crop, as well as the susceptibility of pupae of T. absoluta to EPNs combined with different percentages below the recommended dose of compatible chemical insecticides in laboratory conditions and in the greenhouse. The species of EPN used was Heterorhabditis amazonensis JPM4. The insecticides used were Actara®, Premio®, and Warrant®. In the compatibility test between the EPNs and insecticides, the viability and infectivity of the nematodes after contact with the insecticides were evaluated. An assessment of the efficacy of the combined application of different doses of the insecticides and the EPNs on T. absoluta was carried out in the laboratory and greenhouse. The efficacy of the combined application of the insecticides and the EPNs on T. absoluta via soil was carried out at application intervals of 1 and 2 weeks. The EPNs were compatible with the three insecticides tested. In the laboratory, there was an additive effect of the combined application of insecticides and H. amazonensis as the dose of the products increased. In the greenhouse assay, the combined application of EPNs and insecticides induced mortality above 48%, and the combined application of EPNs and Warrant® 75% presented 60% of mortality. The weekly and fortnightly applications were effective in controlling T. absoluta, and there was no difference between the insecticides tested when applied together with the nematodes.

Rose Bengal incorporated to α-cyclodextrin microparticles for photodynamic therapy against the cariogenic microorganism Streptococcus mutans.

Rose Bengal@α-cyclodextrin (RB@α-CD) microparticles (µPs) were prepared and the RB inclusion in α-CD was experimentally demonstrated through infrared, UV-VIS absorption spectroscopy and cyclic voltammetry. The RB inclusion in α-CD was theoretically investigated using classical molecular mechanics calculations, the simulation results showing that RB can be included in both the narrow and wide apertures of the α-cyclodextrin ring with configurations exhibiting average binding energies of about 27 kcal mol-1. The prepared RB@α-CD microparticles were characterized through Scanning Electron Microscopy (SEM) and it was demonstrated that they are highly efficient in the photodynamic therapy against a Streptococcus mutans (the main bacteria of cariogenic dental plaque) suspension, as a concentration of RB@α-CD µPs 10 times smaller than the usual concentration of pure RB is still capable to produce significant antibacterial activity.

Ram semen deterioration by short-term exposure to high altitude is prevented by improvement of antioxidant status.

Ovine reproduction efficiency in herds at high altitude (ha) is lower than that at low altitude (la). In ewes, ha effects are due to hypoxia and oxidative stress. Our aim was to establish the effect of antioxidant vitamin supplementation on semen traits and antioxidant status of rams exposed to short or long time ha. A total of 32 rams native to la (~500 m) were used, 16 were kept at la and the other 16 were brought to ha (~3600 m), where they were placed in the same flock as the ha native rams (n=16). Half of the animals in each group were supplemented daily with vitamins C 600 mg and E 450 IU per os, during the entire experimental period, starting the 4th day after animal's arrival at ha (day 0). At days 0, 30 and 60 of treatment, blood and semen samples were collected for evaluation of antioxidant status and semen standard characteristics. Data were compared within each experimental time by analysis of variance using a general linear model. Elevated concentrations of oxidative stress biomarkers were present in blood from animals maintained at ha. Ejaculates from ha exposed rams showed decreased sperm concentration, progressive motility and viability, in addition to decreased antioxidant status in seminal fluid. A total of 30 days of oral supplementation with vitamins C and E prevented some ha negative effects on semen characteristics, mainly in recently ha exposed rams. It is concluded that exposure of rams to ha negatively affects semen quality, where oxidative stress plays a predominant role. These effects are mainly prevented by oral supplementation of vitamins C and E, which constitutes a simple and cheap alternative to improve semen quality of rams when they are moved to ha.

Invited review: impact of specific nutrient interventions during mid-to-late gestation on physiological traits important for survival of multiple-born lambs.

To improve production efficiency, the sheep meat industry has increased flock prolificacy. However, multiple-born lambs have lower birth weights, increased mortality and reduced growth rate compared with single-born lambs. Lamb mortality is a major issue for livestock farming globally and solutions are required to increase survival to realise the value of increased flock fecundity. Nutrition during gestation can influence maternal-foetal placental nutrient transfer and thus foetal growth and organ/tissue development, as well as improve postnatal productivity. This review covers the challenges and opportunities associated with increased prolificacy, highlights gaps in our knowledge and identifies some opportunities for how targeted intervention with specific nutrients during mid-to-late pregnancy may influence lamb survival and productivity with a specific focus on pasture-based systems. This time frame was selected as intervention strategies in short-time windows post-pregnancy scanning and before lambing to improve lamb survival in high-risk groups (e.g. triplets) are likely to be the most practical and economically feasible options for pasture-based extensive farming systems.

Intravenous maternal -arginine administration to twin-bearing ewes, during late pregnancy, is associated with increased fetal muscle mTOR abundance and postnatal growth in twin female lambs.

The aims of this study were to determine whether parenteral Arg administered to well-fed twin-bearing ewes from 100 to 140 d of pregnancy influences fetal skeletal muscle growth, the abundance and activation of mechanistic target of rapamycin (mTOR) protein, and postnatal muscle growth of the offspring. Ewes fed 100% of NRC-recommended nutrient requirements for twin-bearing ewes were administered an intravenous bolus of either 345 µmol Arg HCl/kg BW or saline solution (Control) 3 times per day. At 140 d of pregnancy (P140), a group of 11 Control and 9 Arg-treated ewes were euthanized and hind leg muscles and longissimus dorsi (LD) were excised and weighed. A sample of LD was snap frozen in liquid nitrogen for later analysis of free AA (FAA) concentration, mTOR abundance and phosphorylation, and biochemical indices (DNA, RNA, and protein content). For the remaining 25 ewes (Arg, = 13, and Control, = 12), Arg administration was continued until the initiation of parturition and ewes were allowed to lamb. Lambs were weaned at postnatal Day 82 and grazed on pasture until postnatal day 153 (PN153), when a subset of 20 lambs ( = 10 per group) was euthanized. At P140, only the psoas major was heavier in the Arg-administered group compared with the Control group. Female lambs from ewes supplemented with Arg (Arg-F) had increased abundance of total mTOR, RNA concentration, and RNA:DNA ratio in LD compared with female lambs from Control ewes (Con-F), whereas males did not differ. At PN153, Arg-F were heavier than Con-F and had heavier LD and plantaris and a trend for heavier psoas major muscles compared with Con-F. In contrast, BW and individual muscle weights did not differ in male lambs. Lambs from Arg-treated ewes had heavier semimembranosus and tended to have heavier biceps femoris compared with Control lambs. The RNA concentration in LD was greater in Arg-F compared with Con-F, and DNA concentration was greater in the Arg group compared with the Control group. In conclusion, Arg administration to the ewe during gestation increases female lamb weight and muscle weight after birth and these changes are associated with altered mTOR protein abundance and have potential implications for sheep production.

Inflammation and neurogenesis in temporal lobe epilepsy.

The aim of the present review is to discuss the evidence supporting the hypothesis that inflammation and neurogenesis play an important role in temporal lobe epilepsy (TLE) and to examine whether possible strategies that involve the pharmacological manipulation of inflammation/neurogenesis can lead to the development of novel approaches for the treatment of epilepsy. Since it is not yet clear whether the neuron-glia response obtained in this pathology is a secondary effect of an aggressive inflammation or if it is somehow related to the cause of the epileptic condition, with the present review we guide the readers through the complex and ambiguous crosstalk between neuroimmunology and epilepsy.

Nutritional plane of twin-bearing ewes alters fetal mammary gland biochemical composition and mTOR/MAPK pathway signaling.

Identifying the biochemical changes and molecular pathways that regulate fetal mammary development in response to maternal nutrition is important for understanding the link between fetal programming of mammary development and future lactation performance. Although there are published studies regarding biochemical changes in the developing mammary gland, there are currently no data on molecular pathway involvement in regulating ruminant fetal mammary development. This study investigated changes in fetal mammary biochemical indices and mechanistic target of rapamycin (mTOR)/mitogen activated protein kinase (MAPK) signaling at d 100 and 140 of gestation in an ovine model of restricted maternal nutrition. Ewes were randomly allocated to ad libitum (A) or maintenance (M) nutritional regimens, under New Zealand pastoral grazing conditions, from d 21 to 140 of pregnancy. At d 100 and 140 of pregnancy, a subgroup of twin-bearing dams was euthanized, and whole fetal mammary glands (fiber, skin, fat, and ducts) were collected. Mammary glands of fetuses carried by M-fed dams were heavier at d 100 than those of fetuses carried by A-fed dams ( = 0.03), with no difference in the abundance of mTOR/MAPK signaling proteins observed. At d 140, mammary glands of fetuses carried by M-fed dams were lighter ( = 0.07) than fetuses carried by A-fed dams because of decreased hyperplasia ( = 0.04) and hypertrophy ( = 0.09) but had increased protein synthetic capacity ( = 0.02). Increased protein synthetic capacity was associated with increased abundance of MAPK pathway signaling proteins eukaryotic intiation factor 4E (eIF4E)/eIF4E and mTOR pathway signaling proteins eukaryotic initiation factor 4E-binding protein 1 (4E-BP1)/4E-BP1 and ribosomal protein S6 (RPS6)/RPS6 ( ≤ 0.05). Increased abundance of MAPK/mTOR pathway proteins is proposed to mediate increased protein synthetic capacity via ribosome biogenesis and the availability of factors required to initiate protein translation. The primary regulator of 4E-BP1 phosphorylation at Ser65 and RPS6 at Ser235/236 is the activated form of mTOR: mTOR. To study potential tissue-specific mTOR, mTOR abundance mammary glands, separated into parenchyma and fat pad, were collected from d 140 fetuses carried by dams fed a lucerne-based pellet diet formulated to meet 100% of the NRC-recommended maintenance requirements. Results showed that the abundance of mTOR was primarily localized to the fat pad, indicating that the fat pad plays a potential role in regulating development of the fetal mammary gland.

Intravenous maternal -arginine administration to twin-bearing ewes during late pregnancy enhances placental growth and development.

This study aimed to investigate if intravenous maternal Arg administration to well-fed twin-bearing ewes, from 100 to 140 d of gestation or birth, could enhance placental development and placental nutrient transport. Ewes received intravenous infusions of saline (control) or 345 µmol Arg HCl/kg of BW 3 times daily from d 100 of pregnancy (P100) to d 140 of pregnancy (P140; cohort 1) or from P100 to birth (cohort 2). At P140, ewes in cohort 1 were euthanized and individual placentae per fetus were dissected and placentomes were classed per type (A to D) and size (light to heavy). Placentome number and individual weight were recorded. As an indicator of placental nutrient transport, blood plasma was collected from the uterine ovarian vein (UOV), uterine artery (UA), and umbilical vein and artery at the time of euthanasia and analyzed for metabolites and free AA concentrations. The ewes in cohort 2 were allowed to lamb and lambs were weighed at birth. The expelled placenta was dissected and number of cotyledons and weights of total cotyledons, remaining fetal membranes, and total placenta were recorded. At P140, Arg-infused ewes had a 63% ( = 0.03) greater number of unoccupied caruncles than control ewes. No differences were observed for placental weight at P140. At birth, lambs from Arg-infused ewes tended to have 11% ( = 0.09) greater placental weight and 34% ( = 0.03) greater total cotyledon weight compared with control lambs. Arginine-infused ewes (Arg-infused) had increased concentrations of Arg ( = 0.0001) and ornithine (Orn; = 0.004) but decreased concentrations of Met ( = 0.01) and His ( = 0.02 and = 0.09, respectively) compared with control ewes in plasma UOV and UA. Fetuses from Arg-infused ewes had increased concentrations of Orn ( = 0.005) and decreased concentrations of His ( = 0.006), Met ( = 0.003), and Lys ( = 0.01) but no differences in Arg ( > 0.10) concentrations were found compared with control fetuses in umbilical artery and vein plasma. This study showed that maternal Arg administration of well-fed twin-bearing ewes during late pregnancy tended to improve placental growth and development.