Effect of enzyme supplementation of broiler diets based on corn and soybeans

Digestibility of diets based on corn and soybean meal or soybeans treated by roasting or extrusion, with or without an enzyme supplementation, was measured by true (Sibbald) methods, by analysis of excreta, and by analysis of ileal digesta. Only analysis of ileal digesta was able to consistently measure differences between soybean and enzyme treatments in the digestibility of CP, starch, fat, and ME. The amino acid (AA) digestibility of the diets was measured by analysis of the ileal contents. Whereas enzyme supplementation improved overall CP digestibility by 2.9%, this improvement was not equal for all AA. of the AA most important for broilers fed corn-soybean diets, the digestibilities of Lys, Met, and Arg were not improved or not improved significantly by the enzyme supplementation; however, that of Val was improved by 2.3% and that of Thr was improved by 3.0%. A performance trial demonstrated that enzyme supplementation with equal diet formulation improved BW and the feed conversion ratio by 1.9 and 2.2%, respectively. A second performance trial compared standard diet formulations with formulations using enzyme supplementation and energy levels that were reduced by the amount of improvement provided by the inclusion of enzyme in the first performance trial. No difference was seen between treatments, showing that the improvement of nutrient utilization brought about by enzyme supplementation completely compensated for the reduced energy content. Whereas enzyme supplementation should allow a reduction in CP formulation as well, individual AA were not improved equally by supplementation and should also be balanced.

Isolation and sequence determination of peptides in the venom of the spider wasp (Cyphononyx dorsalis) guided by matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry

Micro-scale (sub-pmol) isolation and sequence determination of three peptides from the venom of the solitary spider wasp Cyphononyx dorsalis is described. We isolated two novel peptides Cd-125 and Cd-146 and a known peptide Thr(6)-bradykinin from only two venom sacs of solitary spider wasp Cyphononyx dorsalis without bioassay-guided fractionation. but instead guided by MALDI-TOF MS. The MALDI-TOF MS analysis of each fraction showed the purity and molecular weight of the components, which led to the isolation of the peptides virtually without loss of sample amount. The sequences of the novel peptides Cd-125 (Asp-Thr-Ala-Arg-Leu-Lys-Trp-His) and Cd-146 (Ser-Glu-Thr-Gly-Asn-Thr-Val-Thr-Val-Lys-Gly-Phe-Ser-Pro-Leu-Arg) were determined by Edman degradation together with mass spectrometry. and finally corroborated by solid-phase synthesis. The known peptide Thr(6)-bradykinin (Arg-Pro-Pro-Gly-Phe-Thr-Pro-Phe-Arg) was identified by comparison with the synthetic authentic specimen. This is the first example for any kinins to be found in Pompilidae wasp venoms. The procedure reported here can be applicable to studies on many other components of solitary wasp venoms with limited sample availability. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Eumenitin, a novel antimicrobial peptide from the venom of the solitary eumenine wasp Eumenes rubronotatus

A novel antimicrobial peptide, eumenitin, was isolated from the venom of the solitary eumenine wasp Eumenes rubronotatus. The sequence of eumenitin, Leu-Asn-Leu-Lys-Gly-Ile-Phe-Lys-Lys-Val-Ala-Ser-Leu-Leu-Thr, was mostly analyzed by mass spectrometry together with Edman degradation, and corroborated by solid-phase synthesis. This peptide has characteristic features of cationic linear a-helical antimicrobial peptides, and therefore, can be predicted to adopt an amphipathic a-helix secondary structure. In fact, the CD spectra of eumenitin in the presence of TFE or SDS showed a high content of alpha-helical conformation. Eumenitin exhibited inhibitory activity against both Gram-positive and Gram-negative bacteria, and moderately stimulated degranulation from the rat peritoneal mast cells and the RBL-2H3 cells, but showed no hemolytic activity against human erythrocytes. This antimicrobial peptide in the eumenine wasp venom may play a role in preventing potential infection by microorganisms during prey consumption by their larvae. (c) 2006 Elsevier B.V. All rights reserved.

Diversidade de bactérias de solo sob vegetação natural e cultivo de hortaliças

The microorganisms are essential components in the maintenance of the biological and physicochemical balance of the soil. They exert important function including the degradation of residues of plants and animals and the release of nutrients in the alimentary chain. This work had as objective to compare the microbiota of a soil under bush covering (SMS) and other cropped with vegetables (SHC), suppressive or not it Rhizoctonia solani. Total microbial community DNA was extracted of soils, amplification for PCR of the genes 16S rDNA, inserted into pGEM (R)-T cloning vector and sequencing of the genes of the ribosomal RNA. The analysis of the results demonstrated that this methodology was efficient for evaluation of bacteria in ground. In the bush soil suppressive the microorganisms more found belonged to the phyla of the Acidobacterias, Verrucomicrobia and Actinobacterias and in the soil cultivated with vegetables the biggest frequency was of organisms pertaining to the phyla of the Proteobacterias, Firmicutes and Bacteroidetes.

Impact of sewage sludge on the soil bacterial communities by DNA microarray analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Challenges of modeling depth-integrated marine primary productivity over multiple decades: A case study at BATS and HOT

The performance of 36 models (22 ocean color models and 14 biogeochemical ocean circulation models (BOGCMs)) that estimate depth-integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ (14)C data at the Bermuda Atlantic Time series Study (BATS) and the Hawaii Ocean Time series (HOT) over nearly two decades. Specifically, skill was assessed based on the models' ability to estimate the observed mean, variability, and trends of NPP. At both sites, more than 90% of the models underestimated mean NPP, with the average bias of the BOGCMs being nearly twice that of the ocean color models. However, the difference in overall skill between the best BOGCM and the best ocean color model at each site was not significant. Between 1989 and 2007, in situ NPP at BATS and HOT increased by an average of nearly 2% per year and was positively correlated to the North Pacific Gyre Oscillation index. The majority of ocean color models produced in situ NPP trends that were closer to the observed trends when chlorophyll-alpha was derived from high-performance liquid chromatography (HPLC), rather than fluorometric or SeaWiFS data. However, this was a function of time such that average trend magnitude was more accurately estimated over longer time periods. Among BOGCMs, only two individual models successfully produced an increasing NPP trend (one model at each site). We caution against the use of models to assess multiannual changes in NPP over short time periods. Ocean color model estimates of NPP trends could improve if more high quality HPLC chlorophyll-alpha time series were available.

Comparative time-course study of aminoacyl- and dipeptidyl-resin hydrolysis

The classic hydrolysis procedure for quantification of resin-bound aminoacyl and peptidyl groups with 12 N HCl: propionic acid was recvaluated by studying the influence of the nature of the resin and the resin-bound group. Their stability during acid hydrolysis was dependent on the C-terminal amino acid, and the order of acid stability was Phe > Val > Gly. Otherwise, the dipeptides Ala-Gly, Ala-Val, and Ala-Phe displayed enhanced rates of hydrolysis of the resin if compared with their parent aminoacyl groups. Amongthe resins assayed, the order of acid stability was: benzhydrylamine-resin > p-methylbenzhydrylamine-resin ≅4-(oxymethyl)-phenylacetamidomethyl-resin > chloromethyl-copolymer of styrene-1%-divinylbenzene. Important for peptide synthesis method, the findings demonstrate that longer hydrolysis times than previously recommended in the literature (1 h at 130°C and 15 min at 160°C for peptides attached to the chloromethyl-copolymer of styrene-1%-divinylbenzene) are necessary for the quantitative acid-catalyzed cleavage of some resin-bound groups. The observed broad range of hydrolysis time varied from less than 1 h to about 100 h.

Further triterpenes, steroids and furocoumarins from Brazilian medicinal plants of Dorstenia genus (Moraceae)

The hexane-soluble fractions from the rhizomes or from the leaves from five Dorstenia (Moraceae) species (D. bahiensis Kl., D. bryoniifolia Mart ex. Miq., D. carautae C.C.Berg, D. cayapiaa Vell. and D. heringerii Car. & Val) were analysed by HRGC-MS (high-resolution gas chromatography - mass spectrometry). Pentacyclic triterpenes, steroids and furocoumarins were identified. HRGC-MS is shown to be a valuable tool for the analysis of terpenoidal compounds from Dostenia species. These compounds may be related to the folk utilization of Dorstenia species as antiophidicals.

Short interspersed repetitive elements (SINEs) from the cichlid fish, Oreochromis niloticus, and their chromosomal localization by fluorescent in situ hybridization

In the present study, we describe the cloning and characterization of a new SINE-like element from O. niloticus (ROn-2) and show the distribution of this SINE and a previously isolated SINE, ROn-1, in the chromosomes of O. niloticus. The ROn-2 element is 359 base pairs (bp) in length, contains short direct terminal repeats, a tRNA-related region similar to tRNA Val and tRNA Arg, a tRNA-unrelated region, and a poly-A tail. Analysis of the chromosomal distribution of ROn-1 and ROn-2 by fluorescent in situ hybridization showed that both SINE sequences are present in all chromosomes of tilapia, and organized in small clusters. The only exception was a large cluster of ROn-1 repeats found in the middle of the long arm of chromosome 1. In view of our data we discuss the hypothesis that the absence of large clusters of SINE sequences and the structural composition of these sequences may explain the absence of base-specific fluorochrome bands in the chromosomes of tilapia.

Stochastic Stability for Markovian Jump Linear Systems Subject to a Crucial Failure Event

This paper is concerned with the stability of discrete-time linear systems subject to random jumps in the parameters, described by an underlying finite-state Markov chain. In the model studied, a stopping time τ Δ is associated with the occurrence of a crucial failure after which the system is brought to a halt for maintenance. The usual stochastic stability concepts and associated results are not indicated, since they are tailored to pure infinite horizon problems. Using the concept named stochastic τ-stability, equivalent conditions to ensure the stochastic stability of the system until the occurrence of τ Δ is obtained. In addition, an intermediary and mixed case for which τ represents the minimum between the occurrence of a fix number N of failures and the occurrence of a crucial failure τ Δ is also considered. Necessary and sufficient conditions to ensure the stochastic τ-stability are provided in this setting that are auxiliary to the main result.

Conformational basis for the biological activity of TOAC-labeled angiotensin II and bradykinin: Electron paramagnetic resonance, circular dichroism, and fluorescence studies

N-Terminally and internally labeled analogues of the hormones angiotensin (AII, DRVYIHPF) and bradykinin (BK, RPPGFSPFR) were synthesized containing the paramagnetic amino acid 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4- carboxylic acid (TOAC). TOAC replaced Asp 1 (TOAC 1-AII) and Val 3 (TOAC 3-AII) in AII and was inserted prior to Arg 1 (TOAC 0-BK) and replacing Pro 3 (TOAC 3-BK) in BK. The peptide conformational properties were examined as a function of trifluoroethanol (TFE) content and pH. Electron paramagnetic resonance spectra were sensitive to both variables and showed that internally labeled analogues yielded rotational correlation times (TC) considerably larger than N-terminally labeled ones, evincing the greater freedom of motion of the N-terminus. In TFE, τ C increased due to viscosity effects. Calculation of τ Cpeptide/τ CTOAC ratios indicated that the peptides acquired more folded conformations. Circular dichroism spectra showed that, except for TOAC 1-AII in TFE, the N-terminally labeled analogues displayed a conformational behavior similar to that of the parent peptides. In contrast, under all conditions, the TOAC 3 derivatives acquired more restricted conformations. Fluorescence spectra of All and its derivatives were especially sensitive to the ionization of Tyr 4. Fluorescence quenching by the nitroxide moiety was much more pronounced for TOAC 3-AII The conformational behavior of the TOAC derivatives bears excellent correlation with their biological activity, since, while the N-terminally labeled peptides were partially active, their internally labeled counterparts were inactive [Nakaie, C. R., et al., Peptides 2002, 23, 65-70]. The data demonstrate that insertion of TOAC in the middle of the peptide chain induces conformational restrictions that lead to loss of backbone flexibility, not allowing the peptides to acquire their receptor-bound conformation. © 2004 Wiley Periodicals, Inc.

The LQ control problem for Markovian jumps linear systems with horizon defined by stopping times

This paper deals with a stochastic optimal control problem involving discrete-time jump Markov linear systems. The jumps or changes between the system operation modes evolve according to an underlying Markov chain. In the model studied, the problem horizon is defined by a stopping time τ which represents either, the occurrence of a fix number N of failures or repairs (TN), or the occurrence of a crucial failure event (τΔ), after which the system is brought to a halt for maintenance. In addition, an intermediary mixed case for which T represents the minimum between TN and τΔ is also considered. These stopping times coincide with some of the jump times of the Markov state and the information available allows the reconfiguration of the control action at each jump time, in the form of a linear feedback gain. The solution for the linear quadratic problem with complete Markov state observation is presented. The solution is given in terms of recursions of a set of algebraic Riccati equations (ARE) or a coupled set of algebraic Riccati equation (CARE).

Linear quadratic Gaussian control of discrete-time Markov jump linear systems with horizon defined by stopping times

The linear quadratic Gaussian control of discrete-time Markov jump linear systems is addressed in this paper, first for state feedback, and also for dynamic output feedback using state estimation. in the model studied, the problem horizon is defined by a stopping time τ which represents either, the occurrence of a fix number N of failures or repairs (T N), or the occurrence of a crucial failure event (τ δ), after which the system paralyzed. From the constructive method used here a separation principle holds, and the solutions are given in terms of a Kalman filter and a state feedback sequence of controls. The control gains are obtained by recursions from a set of algebraic Riccati equations for the former case or by a coupled set of algebraic Riccati equation for the latter case. Copyright © 2005 IFAC.

γ-Radiation induces apoptosis via sarcoplasmatic reticulum in guinea pig ileum smooth muscle cells

We investigated the effects of γ-radiation on cells isolated from the longitudinal smooth muscle layer of the guinea pig ileum, a relatively radioresistant tissue. Single doses (up to 50 Gy) reduced the amount of sarcoplasmatic reticulum and condensed the myofibrils, as shown by electron microscopy 3 days post-irradiation. After that, contractility of smooth muscle strips was reduced. Ca2+ handling was altered after irradiation, as shown in fura-2 loaded cells, with elevated basal intracellular Ca2+, reduced amount of intrareticular Ca2+, and reduced capacitive Ca2+ entry. Radiation also induced apoptosis, judged from flow cytometry of cells loaded with proprium iodide. Electron microscopy showed that radiation caused condensation of chromatin in dense masses around the nuclear envelope, the presence of apoptotic bodies, fragmentation of the nucleus, detachment of cells from their neighbors, and reductions in cell volume. Radiation also caused activation of caspase 12. Apoptosis was reduced by the administration of the caspase inhibitor Z-Val-Ala-Asp-fluoromethyl-ketone methyl ester (Z-VAD-FMK) during the 3 day period after irradiation, and by the chelator of intracellular Ca2+, 1,2-bis(o-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid (BAPTA), from 1 h before until 2 h after irradiation. BAPTA also reduced the effects of radiation on contractility, basal intracellular Ca2+, amount of intrareticular Ca2+, capacitative Ca2+ entry, and apoptosis. In conclusion, the effects of gamma radiation on contractility, Ca2+ handling, and apoptosis appear due to a toxic action of intracellular Ca2+. Ca2+-induced damage to the sarcoplasmatic reticulum seems a key event in impaired Ca2+ handling and apoptosis induced by γ-radiation. © 2008 Elsevier B.V. All rights reserved.

Molecular identification of fungal communities in a soil cultivated with vegetables and soil suppressiveness to Rhizoctonia solani

Fungi constitute an important part of the soil ecosystem, playing key roles in decomposition, cycling processes, and biotic interactions. Molecular methods have been used to assess fungal communities giving a more realistic view of their diversity. For this purpose, total DNA was extracted from bulk soils cultivated with tomato (STC), vegetables (SHC), and native forest (SMS) from three sites of the Taquara Branca river basin in Sumaré County, São Paulo State, Brazil. This metagenomic DNA was used as a template to amplify fungal 18S rDNA sequences, and libraries were constructed in Escherichia coli by cloning PCR products. The plasmid inserts were sequenced and compared to known rDNA sequences in the GenBank database. Of the sequenced clones, 22 were obtained from the SMS sample, 18 from the SHC sample, and 6 from the STC sample. Although most of the clone sequences did not match the sequences present in the database, individual amplified sequences matched with Glomeromycota (SMS), Fungi incertae sedis (SMS), and Neocallimastigomycota (SHC). Most of the sequences from the amplified taxa represent uncultured fungi. The molecular analysis of variance (AMOVA) indicated that fluctuations observed of haplotypes in the composition may be related to herbicide application. © 2013 Silvana Pompéia Val-Moraes et al.