961 resultados para Exogenous FSH dosage


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Relationships between endogenous levels of polyamines by thin layer chromatography (TLC) and gas chromatography (GC), nitrate and response to the application of ethylene were established between organic and conventional vegetables (broccoli, collard greens, carrots and beets), both raw and cooked. Responses to ethylene showed that organic plants were less responsive to the growth regulator. The levels of free polyamines obtained by TLC were higher in organic vegetables. Organic broccoli showed higher levels of putrescine (Put), and cooking resulted in lowering the overall content of these amines. Conventional collard green showed the highest level of putrescine in the leaves compared with organic. Tubers of carrots and beets contain the highest levels of Put. These plants also contain high levels of spermine. GC analysis showed the highest polyamines contents compared with those obtained by TLC. Cooking process decreased putrescine and cadaverine content, both in conventionally and organically grown vegetables. Organic beets contain lower NO3(-) compared with its conventional counterpart.

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The aim of the research was to study the effects of exogenous polyamines putrescine, spermidine and spermine and ethylene on in vitro morphogenesis of Aechmea distichantha (Bromeliaceae). The plants obtained in vitro by shoots division were transferred to MS growth regulators free, MS + 10 μmol Put, MS + 10 μmol Spd, MS + 10 μmol Spm, MS + 10 mg/L ethylene and MS + 20 mg/L ethylene. Plants were harvest after 0, 15, 30, 45 and 60 days of culture. Number of shoots and roots and endogenous concentrations of polyamines Put, Spd and Spm, protein and peroxidase activity in leaves were evaluated. Spd stimulated shoots formation on A. Distichantha. All treatments had deleterious effect on rhizogenesis. Plants treated with polyamines had higher proteins levels when compared to ethylene indicating the growing and development of explants. Ethylene treatment had no effect on polyamines levels. Thus, the biosynthetic routes of ethylene and polyamines may not compete for the common precursor S-adenosylmethionine.

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BACKGROUND: Cellulose and hemicellulose are quantitatively the most important structural carbohydrates present in ruminant diets. Rumen micro-organisms produce enzymes that catalyse their hydrolysis, but the complex network formed by structural carbohydrates and lignin reduces their digestibility and restricts efficient utilisation of feeds by ruminants. This study aimed to produce two enzymatic extracts, apply them in ruminant diets to determine the best levels for ruminal digestibility and evaluate their effects on in vitro digestibility. RESULTS: In experiment 1 a two-stage in vitro technique was used to examine the effects of different enzymatic levels of Aspergillus japonicus and Aspergillus terricola on tropical forages. Enzyme addition had minor effects on corn silage at the highest enzymatic level. In experiment 2 an in vitro gas production (GP) technique was applied to determine apparent in vitro organic matter digestibility and metabolisable energy. The addition of enzymes in GP showed interesting results. Good data were obtained using sugar cane and Tifton-85 hay supplemented with extracts of A. japonicus and A. terricola respectively. CONCLUSION: Overall, the study suggests that addition of crude extracts containing exogenous fibrolytic enzymes to ruminant diets enhances the effective utilisation of ruminant feedstuffs such as forages. Copyright (c) 2012 Society of Chemical Industry

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Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate-release (IR) solid oral dosage forms containing stavudine (d4T) are reviewed. According to Biopharmaceutics Classification System (BCS), d4T can be assigned to BCS class I. No problems with BE of IR d4T formulations containing different excipients and produced by different manufacturing methods have been reported and, hence, the risk of bioinequivalence caused by these factors appears to be low. Furthermore, d4T has a wide therapeutic index. It is concluded that a biowaiver is appropriate for IR solid oral dosage forms containing d4T as the single active pharmaceutical ingredient (API) provided that (a) the test product contains only excipients present in the IR d4T drug products that have been approved in a number of countries for the same dosage form, and (b) both test product and its comparator are either very rapidly dissolving or rapidly dissolving with similarity of dissolution profiles demonstrated at pH 1.2, 4.5, and 6.8. (c) 2011 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:1016, 2012

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The 15-deoxy-(Delta 12,14)-PG J(2) (15d-PGJ(2)) has demonstrated excellent anti-inflammatory results in different experimental models. It can be used with a polymeric nanostructure system for modified drug release, which can change the therapeutic properties of the active principle, leading to increased stability and slower/prolonged release. The aim of the current study was to test a nano-technological formulation as a carrier for 15d-PGJ(2), and to investigate the immunomodulatory effects of this formulation in a mouse periodontitis model. Poly (D, L-lactide-coglycolide) nanocapsules (NC) were used to encapsulate 15d-PGJ(2). BALB/c mice were infected on days 0, 2, and 4 with Aggregatibacter actinomycetemcomitans and divided into groups (n = 5) that were treated daily during 15 d with 1, 3, or 10 mu g/kg 15d-PGJ(2)-NC. The animals were sacrificed, the submandibular lymph nodes were removed for FACS analysis, and the jaws were analyzed for bone resorption by morphometry. Immunoinflammatory markers in the gingival tissue were analyzed by reverse transcriptase-quantitative PCR, Western blotting, or ELISA. Infected animals treated with the 15d-PGJ(2)-NC presented lower bone resorption than infected animals without treatment (p < 0.05). Furthermore, infected animals treated with 10 mu g/kg 15d-PGJ(2)-NC had a reduction of CD4(+)CD25(+)FOXP3(+) cells and CD4/CD8 ratio in the submandibular lymph node (p < 0.05). Moreover, CD55 was upregulated, whereas RANKL was downregulated in the gingival tissue of the 10 mu g/kg treated group (p < 0.05). Several proinflammatory cytokines were decreased in the group treated with 10 mu g/kg 15d-PGJ(2)-NC, and high amounts of 15d-PGJ(2) were observed in the gingiva. In conclusion, the 15d-PGJ(2)-NC formulation presented immunomodulatory effects, decreasing bone resorption and inflammatory responses in a periodontitis mouse model. The Journal of Immunology, 2012, 189: 1043-1052.

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The role of the delta-ornithine amino transferase (OAT) pathway in proline synthesis is still controversial and was assessed in leaves of cashew plants subjected to salinity. The activities of enzymes and the concentrations of metabolites involved in proline synthesis were examined in parallel with the capacity of exogenous ornithine and glutamate to induce proline accumulation. Proline accumulation was best correlated with OAT activity, which increased 4-fold and was paralleled by NADH oxidation coupled to the activities of OAT and Delta(1)-pyrroline-5-carboxylate reductase (P5CR), demonstrating the potential of proline synthesis via OAT/P5C. Overall, the activities of GS. GOGAT and aminating GDH remained practically unchanged under salinity. The activity of P5CR did not respond to NaCl whereas Delta(1)-pyrroline-5-carboxylate dehydrogenase was sharply repressed by salinity. We suggest that if the export of P5C from the mitochondria to the cytosol is possible, its subsequent conversion to proline by P5CR may be important. In a time-course experiment, proline accumulation was associated with disturbances in amino acid metabolism as indicated by large increases in the concentrations of ammonia, free amino acids, glutamine, arginine and ornithine. Conversely, glutamate concentrations increased moderately and only within the first 24 h. Exogenous feeding of ornithine as a precursor was very effective in inducing proline accumulation in intact plants and leaf discs, in which proline concentrations were several times higher than glutamate-fed or salt-treated plants. Our data suggest that proline accumulation might be a consequence of salt-induced increase in N recycling, resulting in increased levels of ornithine and other metabolites involved with proline synthesis and OAT activity. Under these metabolic circumstances the OAT pathway might contribute significantly to proline accumulation in salt-stressed cashew leaves. (C) 2011 Elsevier GmbH. All rights reserved.

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Pinus taeda wood chips were treated with the biopulping fungus Ceriporiopsis subvermispora in calcium-or oxalic acid-amended cultures. The secretion of hydrolytic and oxidative enzymes was inhibited only in the cultures having the highest concentration of calcium (1400 mg kg(-1) wood). Calcium decreased the availability of free oxalic acid, inhibited fungal growth, and reduced lignin mineralization and transformations. Oxalic acid amendment in the cultures was found not to affect the lignin mineralization and transformations; however, it did inhibit the depolymerization reactions detectable in the residual lignin that was retained in the biotreated wood. C. subvermispora presented catabolic activity for oxalic acid in the cultures amended with 1660 mg acid kg(-1) wood, whereas oxalic acid was synthesized when it was amended at low amounts or initially absent in the cultures. These data suggest one ideal ratio of oxalic acid in C. subvermispora cultures and indicate that its exogenous addition does not necessarily accompany the further degradation of lignin. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.

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Plant secondary metabolites are a group of naturally occurring compound classes biosynthesized by differing biochemical pathways whose plant content and regulation is strongly susceptible to environmental influences and to potential herbal predators. Such abiotic and biotic factors might be specifically induced by means of various mechanisms, which create variation in the accumulation or biogenesis of secondary metabolites. Hence the dynamic aspect of bioactive compound synthesis and accumulation enables plants to communicate and react in order to overcome imminent threats. This contribution aims to review the most important mechanisms of various abiotic and biotic interactions, such as pathogenic microorganisms and herbivory, by which plants respond to exogenous influences, and will also report on time-scale variable influences on secondary metabolite profiles. Transmission of signals in plants commonly occurs by 'semiochemicals', which are comprised of terpenes, phenylpropanoids, benzenoids and other volatile compounds. Due to the important functions of volatile terpenes in communication processes of living organisms, as well as its emission susceptibility relative to exogenous influences, we also present different scenarios of concentration and emission variations. Toxic effects of plants vary depending on the level and type of secondary metabolites. In farming and cattle raising scenarios, the toxicity of plant secondary metabolites and respective concentration shifts may have severe consequences on livestock production and health, culminating in adverse effects on crop yields and/or their human consumers, or have an adverse economic impact. From a wider perspective, herbal medicines, agrochemicals or other natural products are also associated with variability in plant metabolite levels, which can impact the safety and reliable efficacy of these products. We also present typical examples of toxic plants which influence livestock production using Brazilian examples of toxicity of sapogenins and alkaloids on livestock to highlight the problem. (c) 2012 Elsevier B.V. All rights reserved.

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Objectives: To evaluate the effects of folic acid supplementation on isolated oral cleft recurrence and fetal growth. Patients and Methods: The study included 2,508 women who were at-risk for oral cleft recurrence and randomized into two folic acid supplementation groups: 0.4 and 4 mg per day before pregnancy and throughout the first trimester. The infant outcome data were based on 234 live births. In addition to oral cleft recurrence, several secondary outcomes were compared between the two folic acid groups. Cleft recurrence rates were also compared to historic recurrence rates. Results: The oral cleft recurrence rates were 2.9% and 2.5% in the 0.4 and 4 mg groups, respectively. The recurrence rates in the two folic acid groups both separately and combined were significantly different from the 6.3% historic recurrence rate post the folic acid fortification program for this population (p = 0.0009 when combining the two folic acid groups). The rate of cleft lip with palate recurrence was 2.9% in the 0.4 mg group and 0.8% in the 4 mg group. There were no elevated fetal growth complications in the 4 mg group compared to the 0.4 mg group. Conclusions: The study is the first double-blinded randomized clinical trial (RCT) to study the effect of high dosage folic acid supplementation on isolated oral cleft recurrence. The recurrence rates were similar between the two folic acid groups. However, the results are suggestive of a decrease in oral cleft recurrence compared to the historic recurrence rate. A RCT is still needed to identify the effect of folic acid on oral cleft recurrence given these suggestive results and the supportive results from previous interventional and observational studies, and the study offers suggestions for such future studies. The results also suggest that high dosage folic acid does not compromise fetal growth

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The pulmonary surfactant has essential physical properties for normal lung function. The most important property is the surface tension. In this work, it was evaluated the surface tension of two commercial exogenous surfactants used in surfactant replacement therapy, poractant alfa (Curosurf, Chiesi Farmaceuticals, Italy) and beractant (Survanta, Abbott Laboratories, USA) using new parameters. A Langmuir film balance (Minitrough, KSV Instruments, Finland) was used to measure surface tension of poractant alfa and beractant samples. For both samples, we prepared a solution of 1 mg/m dissolved in chloroform (100π`), which was applied over a subphase of milli-Q water (175 ml) in the chamber of the balance. The chamber has two moving barriers that can change its surface area between a maximal value of 112.5 cm 2 , and a minimal value of 22.5 cm 2, defining a balance cycle. Each surfactant had its surface tension evaluated during 20 balance cycles for three times. Four quantities were calculated from the experiment: Minimum Surface Tension (MTS), defined as the surface tension at minimal surface area during the first cycle; Mean Work Cycle (MWC), defined as the mean hysteresis area of the measured surface tension curve of the last 16 balance cycles; Critical Active Surface Area in Compression (CASAC) or in Expansion (CASAE), defined as the maximal chamber area where the surfactant is active on the surface in compression or expansion. The t-test was applied to verify for statistical significance of the results. Comproved with the MST is the same reported in literature, the differences between MWC, CASAC, and CASAE were statistically significant (p<0.001). The MWC, CASAC and CASAE were higher for poractant alfa than for beractant. A higher MWC for poractant alfa means higher elastic recoil of the lung in comparison with beractant. Using a different methodology, our results showed that poractant alfa is probably more effective in a surfactant replacement therapy than beractant due the use of poractant alfa in relation to the use of beractant in preterm infants with Respiratory Distress Syndrome (RDS).

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Rationale: The primary function of surfactant is to reduce the surface tension at air-liquid interface. In this study, the surface tension behavior of two commercial surfactants, poractant alfa (ChiesiFarmaceuticals,ltaly) and beractant (Abbott Laboratories,USA), were evaluated,using new parameters. Methods: We used a Langmuir film balance (Minitrough,KSV lnstruments,Finland) to measure of surface tension of both poractant alfa and beractant samples. For both samples,we prepared a solution of 1 mg/mdl dissolved in chloroform. The solution (1uL) was applied over a subphase of milli-Q water (175 ml) in the chamber of the balance. The chamber has two moving barriers that can change its surface area between a maximum value of 112.5 cm2 anda minimum value of 22.5 cm2, defining a balance cycle.lhree sample's films were evaluated for each sample, during 20 balance cycles. Here quantify two new variables, which is the mean hysteresis area of the measured curve surface tension of the last 16 balance cycles,defined here as Mean Work Cycle (MWC), and the moment that the surfactant is active in the surface, this measure is defined here as Active Surface Area Critical in the compression (ASACC) and the expansion (ASACE). The test was applied to compare the statistical significance of the results.

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Most studies of exogenous visuospatial attention use placeholders indicating the regions where the stimuli appear on the screen. Preliminary results from our laboratory provided evidence that the attentional effect is more frequently observed when placeholders are used in these experimental procedures. Four experiments were carried out. Experiment 1 aimed at confirming the finding that the attentional effect of a spatially non-informative cue (S1) observed in the presence of placeholders disappears in their absence. The results confirmed this finding. Experiments 2, 3, and 4 examined several possible processes that could explain this finding. Experiment 2 investigated if the contribution of a faster disengagement of attention from the cued location or a stronger forward masking could explain the absence of attentional effect when no placeholders were used. Experiment 3 investigated if increased difficulty in discrimination of the target (S2) from S1 would favor the appearance of the attentional effect in the absence of placeholders. Experiment 4 investigated if an insufficient focusing of attention towards the cued location could explain the absence of attentional effect when no placeholders were used. The results of the three experiments indicated that placeholders act by reducing the discriminability of the S2. This would presumably lead to the adoption of an attentional set that favors the mobilization of attention by the S1

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A new formulate containing citokinins, that is commercialized as Cytokin, has been introduced as dormancy breaking agents. During a three-years study, Cytokin was applied at different concentrations and application times in two producing areas of the Emilia-Romagna region to verify its efficacy as a DBA. Cytokin application increased the bud break and showed a lateral flower thinning effect. Moreover, treated vines showed an earlier and more uniform flowering as compared to control ones. Results obtained on the productive performance revealed a constant positive effect in the fruit fresh weight at harvest. Moreover, Cytokin did not cause any phytotoxicity even at the highest concentrations. Starting from the field observation, which suggested the involvement of cytokinins in kiwifruit bud release from dormancy, 6-BA was applied in open field condition and molecular and histological analyses were carried out in kiwifruit buds collected starting from the endo dormant period up to complete bud break to compare the natural occurring situation to the one induced by exogenous cytokinin application. In details, molecular analyses were set up on to verify the expression of genes involved in the reactivation of cell cycle: cyclin D3, histone H4, cyclin-dependent kinase B, as well as of others which are known to be up regulated during bud release in other species, i.e.isopenteniltransferases (IPTs), which catalyze the first step in the CK biosynthesis, and sucrose synthase 1 and A, which are involved in the sugar supplied. Moreover, histological analyses of the cell division rate in kiwifruit bud apical meristems were performed. These analyses showed a reactivation of the cell divisions during bud release and changes in the expression level of the investigated genes.

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This current work focused on the simulation of in vivo dissolution and permeation in order to be able to predict the in vivo performance of orally administered fenofibrate immediate release formulations. Therefore, the effects of the formulation surfactants on in vivo solubility and permeation of fenofibrate under physiologically relevant excipient concentrations were emphasized.rnIt was shown that the surfactant sodium dodecyl sulfate (SDS) may decrease rather than increase the solubility of fenofibrate in vivo. This was related to the interference of SDS with the vesicular system of the biorelevant medium, FaSSIFmod, and therefore its solubilization capacity. rnMoreover, in vitro permeation studies revealed that SDS concentrations inversely correlated with fenofibrate permeability. Through combination of the observed permeation and solubility data a good in vitro/in vivo correlation regarding Cmax values in humans could be established for five fenofibrate formulations which were based on the same manufacturing technique.rnBesides the experimental part, the major characteristics and their potential implementation in a dissolution/permeation device were discussed based on the promising realization of the in vitro solubility and permeation methods. rn