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Lower Capacity (lower + capacity)
Selected AbstractsPharmacokinetics of Gabapentin during Delivery, in the Neonatal Period, and Lactation: Does a Fetal Accumulation Occur during Pregnancy?EPILEPSIA, Issue 10 2005Inger Öhman Summary:,Purpose: To study the pharmacokinetics of gabapentin (GBP) during delivery, lactation, and in the neonatal period. Methods: GBP concentrations in plasma and breast milk were determined with high-performance liquid chromatography in samples from six women treated with GBP and in their offspring. Blood samples were obtained at delivery from mothers, from the umbilical cord, and from the newborns on three occasions during 2 days after delivery. GBP concentration also was determined in breast milk and in blood collected from five of the mothers and suckling infants 2 weeks to 3 months after birth. Results: The umbilical cord/maternal plasma concentration ratios ranged from 1.3 to 2.1 (mean, 1.7). GBP plasma concentrations in the neonates declined with an estimated half-life of 14 h. Mean GBP plasma concentrations in the infants were 27% of the cord plasma levels (range, 12,36%) 24 h postpartum. The mean milk/maternal plasma concentration ratio was 1.0 (range, 0.7,1.3) from 2 weeks to 3 months. The infant dose of GBP was estimated to 0.2,1.3 mg/kg/day, equivalent to 1.3,3.8% of the weight-normalized dose received by the mother. The plasma concentrations in the breast-fed infants were ,12% of the mother's plasma levels, but no adverse effects were observed. Conclusions: Our limited observations suggest an active transplacental transport of GBP, with accumulation in the fetus as a consequence. We suggest that this could be by the specific L-type amino acid transporter 1 (LAT-1), which is expressed in the placenta. Newborns seem to have a slightly lower capacity to eliminate GBP than do adults. Transfer of GBP to breast milk is extensive, but plasma concentrations appear to be low in suckling infants. No adverse effects were observed in the newborn. Although more data are needed, our observations suggest that breastfeeding in conjunction with GBP treatment is safe. [source] Defective T-cell function leading to reduced antibody production in a kleisin-, mutant mouseIMMUNOLOGY, Issue 2 2008Katharine M. Gosling Summary The recently described nessy (Ncaph2nes/nes) mutant mouse strain has a defect in T-cell development caused by a mutation in the ubiquitous kleisin-, (also known as Ncaph2). Kleisin- , is a subunit of the condensin II complex involved in chromosome condensation during mitosis. The nessy phenotype is characterized by CD44hi CD8+ peripheral T cells, 10,20% of normal thymocyte numbers and 2·5-fold fewer ,, T cells in the spleen compared with wild-type mice. In this study we examined the effect of the nessy mutation in kleisin-, on the immune response by challenging mice with an attenuated strain of Salmonella. Results showed that nessy mice control bacterial load as effectively as wild-type mice but exhibit a reduced antibody titre. Further experiments revealed that while the T-dependent antibody response was diminished in nessy mice the T-independent response was normal, suggesting that the defect was the result of T-cell function and not B-cell function. In vitro activation assays showed that nessy T cells have a lower capacity to up-regulate the early activation marker CD69 than wild-type T cells. Upon transfer into RAG,/, mice, nessy and wild-type CD4 T cells showed equivalent homeostatic proliferation, while nessy CD8 T cells proliferated more than their wild-type counterparts. When cultured with anti-T-cell receptor , or concanavalin A, nessy T cells were found to die faster than wild-type T cells. These data indicate that kleisin-, is required for a normal immune response, and represent the first demonstration of a role for kleisin-, in T-cell function. [source] Strategic inventory in capacitated supply chain procurementMANAGERIAL AND DECISION ECONOMICS, Issue 1 2008nar Keskinocak We study the strategic role of inventory in a sequential two-period procurement setting, where the supplier's capacity in the first period is limited and the retailer has the option to hold inventory. We compare the equilibrium under a dynamic contract, where the decisions are made at the beginning of each period, and a commitment contract, where the decisions for both periods are made at the beginning of the first period. We show that there is a critical capacity level below which the outcomes under both types of contracts are identical. When the first period capacity is above the critical level, the retailer holds inventory in equilibrium and the inventory is carried due to purely strategic reasons; as capacity increases, so does the strategic role of inventory. The supplier always prefers lower capacity than the retailer, and the difference between supplier-optimal and supply-chain optimal capacities, and the corresponding profits, can be significant. Finally, we find that the retailer's flexibility to hold inventory is not always good for the participants or for the channel. Copyright © 2008 John Wiley & Sons, Ltd. [source] Combined effects of arbuscular mycorrhizas and light on water uptake of the neotropical understory shrubs, Piper and PsychotriaNEW PHYTOLOGIST, Issue 2 2003Damond A. Kyllo Summary ,,Root hydraulic conductance (Kr) was measured for five understory shrub species of the neotropical moist forest to determine the effects of arbuscular mycorrhizas (AM) for both carbon-rich and carbon-limited host plants. ,,Kr was measured using a high pressure flow meter (HPFM) for potted plants grown in a factorial combination of AM fungi (presence/absence) and light (3.5 and 30% of full sun, low/high). ,,AM colonization improved Kr for the more shade-tolerant species plants when growing in low light. By contrast, water uptake efficiency of the light-demanding species was significantly decreased by AM fungi in high light. Regardless of AM colonization, light-demanding species had a lower capacity than shade-tolerant species to meet transpirational demands, and they allocated substantially more to fine root production relative to leaf area when colonized. ,,The differential effects of AM colonization and light on a species' root hydraulic conductance in relation to phylogeny and light adaptation demonstrate that AM fungi may be critical in determining early plant succession and community composition not only due to effects on nutrient uptake, but on water uptake as well. [source] Ketotic hypoglycemia in patients with allergic diseasesPEDIATRICS INTERNATIONAL, Issue 6 2003Tomoyo Matsubara AbstractBackground:,Ketotic hypoglycemia is the most common cause of recurrent hypoglycemia in early childhood but its etiology is poorly understood. Elimination diets have been used for the prevention or treatment of some allergic diseases; however, these diets entail a risk to the normal nutrition and growth of children. The present study investigated whether elimination diets are related to the occurrence of ketotic hypoglycemia. Methods:,The prevalence of allergy treated with elimination diet therapy was retrospectively investigated in 18 patients with ketotic hypoglycemia seen in Yamaguchi University Hospital between January 1995 and September 1999. Data were gathered by reviewing the patients' medical charts. Results:,Ten (55.6%) of 18 patients with ketotic hypoglycemia had allergic diseases. Six (60%) of the patients had been treated with strict elimination diets and the others were on incomplete elimination diets for the prevention of allergy. The ketotic hypoglycemia patients with allergic diseases had experienced fewer pre-existing infectious diseases than those without allergic diseases. Conclusions:,Patients with allergic diseases treated with elimination diets have a relatively high tendency towards developing ketotic hypoglycemia. They might have a lower capacity to tolerate fasting due to their excessive avoidance of many foods, even during periods when they are not undergoing strict elimination diets. [source] Ovarian Structure in Mice Lines Selected for WeightANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009S. F. Bernardi Summary Selection for body weight at 49 day of age (s and h, downward selected lines; s, and h,, upward selected lines) affected reproductive traits in CF1 mice lines. The objective of this study was to compare ovarian structures in females of these lines, as well as in unselected controls (Line t). The number of ovarian follicles (N), follicle diameter (FD), number of corpora lutea (CL), litter size (LS), and body weight (W), were recorded. There were significant differences among lines for N, FD, CL, LS and W; means values for the lines with the greatest difference for post-pubertal females were: Ns = 19.3 and Ns, = 32.7; FDh, = 161.7 and FDs, = 178.2; CLh = 10.3 and CLs, = 21.9; LSs = 6.0 and LSh, = 11.1; Wh = 18.9 and Ws, = 32.4. There were also differences between positive lines; Line s, had a higher proportion of large follicles in pre-pubertal females, a greater capacity to convert these follicles into CL, but a lower capacity to maintain embryos until term than Line h,. For negative lines, Line h apparently had a reduced incidence of embryonic loss when compared with Line s. In conclusion, selection for body weight modified ovarian structure, as well as reproductive efficiency. [source] Mechanism of insulin action on glucose metabolism in ruminantsANIMAL SCIENCE JOURNAL, Issue 6 2002Shin-ichi SASAKI ABSTRACT This review presents a brief overview on the mechanism of insulin action on glucose metabolism at the molecular basis in ruminants. For ruminants, an exact mechanism of insulin on glucose metabolism is still rudimentary, but it is clear that originally, if not all, the mechanism of insulin action in ruminants was the same as in other species. Like non-ruminants, the insulin-sensitive glucose transporter GLUT 4 is thought to be a key-protein in the control of glucose uptake and metabolism in ruminants, and insulin regulates glucose transport by stimulating the translocation of GLUT 4 from an intracellular membrane pool to the plasma membrane in adipocytes and muscles. Moreover, insulin-induced GLUT 4 translocation is activated through the common intracellular signaling pathway of insulin phosphatidylinositol 3-kinase (PI3-kinase) signaling pathway rather than the mitogen activated protein kinase (MAP kinase)-dependent signaling pathway. However, GLUT 4 mRNA and protein, and insulin-induced GLUT 4 translocation on adipocytes and muscles in ruminants are lower than those in rodents and human subjects. Furthermore, insulin-induced PI3-kinase activation is reduced concomitantly with the lower content of insulin receptor substrate-1 (IRS-1) in ruminants. In spite of normal status, a resistance to the stimulatory action of insulin on glucose metabolism in ruminants as compared to non-ruminants may be due to, at least in part, the lower content of GLUT 4 and the lower capacity of insulin signal transduction, resulting to the lower glucose transport activity. [source] Effect of dietary protein and energy levels on growth, oxygen consumption, haemolymph and digestive gland carbohydrates, nitrogen excretion and osmotic pressure of Litopenaeus vannamei (Boone) and L. setiferus (Linne) juveniles (Crustacea, Decapoda; Penaeidae)AQUACULTURE RESEARCH, Issue 7 2001C Rosas Abstract The influence of protein and energy levels on growth rate, survival, pre- and post-prandial oxygen consumption, ammonia excretion, haemolymph glucose (HG), glycogen in digestive gland and osmotic pressure (OP) in white shrimp Litopenaeus vannamei (Boone) and L. setiferus (Linne) juveniles was studied. Diets containing a high-quality protein at a protein/energy (P/E) ratio of 16, 26, 31 and 36 mg kJ,1 were fed at 20% of shrimp body weight of two sizes: < 1 g and >,1 g. Both species showed a optimum P/E ratio of 36 mg kJ,1 (33,44% protein and 6,23% carbohydrate) in juveniles <,1 g. For shrimp >,1 g, L. setiferus showed a higher growth rate in the diet with 16 mg kJ,1 (27% protein; 32% carbohydrate) and L. vannamei between 26 and 36 mg kJ,1 (33,44% protein and 6,23% carbohydrate). In both experiments, the growth rate of L. vannamei was 2,3 times that observed in L. setiferus. Routine oxygen consumption and apparent heat increment (AHI) of L. setiferus juveniles was two times higher than that observed in L. vannamei juveniles, which could indicate that L. setiferus has a higher metabolic rate. The O/N ratio varied according to protein level, with higher values (O/N = 180) with a 16-mg kJ,1 diet and lower values (O/N = 73) with a 36-mg kJ,1 diet in L. setiferus juveniles. A similar variation in O/N ratio was obtained in L. vannamei fed with all diets with an interval between 22 and 50. An inverse relation between ammonia excretion and HG, and digestive gland glycogen (DGG) in relation to an increase in the P/E ratio indicate that both shrimp species are well adapted to use carbohydrates and/or proteins from their diet. The higher values of hyper-osmotic capacity (hyper-OC) were observed in L. setiferus <,1 g fed with 36 mg kJ,1 and the lowest in L. vannamei <,1 g fed with 31 mg kJ,1. Intermediate values of hyper-OC were observed in both species fed all diets indicating that osmotic factors of juveniles <,1 g of both species are more affected by the P/E ratio than juveniles >,1 g. All results showed that juveniles >,1 g of both species are less dependent of P/E ratio than juveniles <,1 g. Litopenaeus vannamei is a most tolerant shrimp species with a high capacity to use a wide range of dietary P/E ratios for growth, which may be due to its lower energy requirements. Litopenaeus setiferus showed a lower capacity to accept different P/E ratios but the optimum P/E ratio obtained with this species shows that L. setiferus accept diets with a high carbohydrate level as well. These results demonstrate that there are nutritional and physiological differences that explain the differences that have been observed when both species were cultured in commercial ponds. [source] | |||||||||||||