Dipeptide synthesis in biphasic medium: evaluating the use of commercial porcine pancreatic lipase preparations and the involvement of contaminant proteases

Dipeptide syntheses starting from Ac-L-Tyr-OEt or Z-L-X-OMe (X: Asp, Tyr, Phe, Arg, Lys or Thr) and glycine amide in biphasic reaction media were achieved using two commercially available porcine pancreatic lipase (PPL) preparations (crude (cPPL) and purified PPL (pPPL)). Under the mild conditions employed, α-chymotrypsin, a pancreatic protease that also presents esterase activity, catalyzed Ac-L-Tyr-Gly-NH2 synthesis with high productivity. Product hydrolysis also occurred in most of the syntheses studied. Polyacrylamide gel electrophoresis, enzymatic assays employing specific chromogenic substrates and size-exclusion chromatography revealed that cPPL and pPPL contain contaminant proteases and, therefore, exhibit esterase and amidase activities. Overall, these data indicate that those contaminants may be the main catalysts of peptide bond synthesis when Nα-blocked-L-amino acid esters and the commercial PPL preparations are used. On the other hand, such data do not contest the possibility of using such enzyme preparations as an inexpensive source of catalysts for dipeptide synthesis under soft conditions.

Use of Cassava Peel as Carbon Source for Production of Amylolytic Enzymes by Aspergillus niveus

Aspergillus niveus produced high levels of alpha-amylase and glucoamylase in submerged fermentation using the agricultural residue cassava peel as a carbon source. In static conditions, the amylase production was substantially greater than in the agitated condition. The optimized culture conditions were initially at pH 5.0, 35 degrees C during 48 hours. Amylolytic activity was still improved (50%) with a mixture of cassava peel and soluble starch in the proportion 1:1 (w/w). The crude extract exhibited temperature and pH optima approximately 70 degrees C and 4.5, respectively. Amylase activity was stable for 1 h at 60 degrees C, and at pH values between 3.0 and 7.0. The enzyme hydrolysed preferentially maltose, starch, penetrose, amylose, isomaltose, maltotriose, glycogen and amylopectin, and not hydrolysed cyclodextrin (alpha and beta), trehalose and sucrose. In the first hour of reaction on soluble starch, the hydrolysis products were glucose and maltose, but after two hours of hydrolysis, glucose was the unique product formed, confirming the presence in the crude extract of an alpha-amylase and a glucoamylase.

The Use of Latent Semantic Indexing to Mitigate OCR Effects of Related Document Images

Due to both the widespread and multipurpose use of document images and the current availability of a high number of document images repositories, robust information retrieval mechanisms and systems have been increasingly demanded. This paper presents an approach to support the automatic generation of relationships among document images by exploiting Latent Semantic Indexing (LSI) and Optical Character Recognition (OCR). We developed the LinkDI (Linking of Document Images) service, which extracts and indexes document images content, computes its latent semantics, and defines relationships among images as hyperlinks. LinkDI was experimented with document images repositories, and its performance was evaluated by comparing the quality of the relationships created among textual documents as well as among their respective document images. Considering those same document images, we ran further experiments in order to compare the performance of LinkDI when it exploits or not the LSI technique. Experimental results showed that LSI can mitigate the effects of usual OCR misrecognition, which reinforces the feasibility of LinkDI relating OCR output with high degradation.

PRACTICAL USE OF MOLECULAR MARKERS IN BEEF AND DAIRY ZEBU CATTLE IN BRAZIL

Selection of zebu (Bos indicus) beef and dairy cattle in Brazil and the validation process of genetic markers for growth, carcass and meat quality traits and also for milk production, fat and protein milk content are discussed as concerned to the concepts and details of their use as auxiliary tools in selection processes. It is highlighted, also, the importance of right selection of ova donor cows for production of embryos to be transferred.

Use of correlated potential harmonic basis functions for the description of the (4)He trimer and small clusters

A correlated many-body basis function is used to describe the (4)He trimer and small helium clusters ((4)HeN) with N = 4-9. A realistic helium dimer potential is adopted. The ground state results of the (4)He dimer and trimer are in close agreement with earlier findings. But no evidence is found for the existence of Efimov state in the trimer for the actual (4)He-(4)He interaction. However, decreasing the potential strength we calculate several excited states of the trimer which exhibit Efimov character. We also solve for excited state energies of these clusters which are in good agreement with Monte Carlo hyperspherical description. (C) 2011 American Institute of Physics. [doi:10.1063/1.3583365]

Use of blanks to determine in vitro net gas and methane production when using rumen fermentation modifiers

Blanks (flasks without substrate containing only inoculum and medium) are used in vitro to correct for gas. CH(4) and residual organic matter (OM) fermented in inoculum. However inclusion of rumen fermentation modifiers may affect fermentation of OM in the substrate and inoculum. Thus, data correction using blanks that lack additives may result in inaccurate adjustment for background fermentation. Our objective was to evaluate impacts of using blanks containing additive (i.e., specific blanks) or blanks without additive on estimation of in vitro net gas and CH(4) production. We used the semi-automatic in vitro gas production technique including monensin sodium at 2.08 mg/l of buffered rumen fluid (Experiment 1) or carvacrol, eugenol and 1,8-cineol at 667 mg/l (Experiment 2) in flasks with substrate and in blank flasks. At 16h of incubation, monensin reduced (P <= 0.02) total gas production in flasks containing substrate (162.0 ml versus 146.3 ml) and in blanks (84.4 ml versus 79.2 ml). Total methane production was also decreased (P <= 0.05) by adding monensin to flasks containing substrate (15.7 ml versus 11.9 ml) as well as in blanks (6.4 ml versus 5.0 ml). Inclusion of carvacrol or eugenol reduced (P <= 0.05) total gas and CH(4) production in flasks with substrate and in blanks, but in a more pronounced manner than monensin. For these three additives, correction for blank without additive resulted in lower net gas and CH(4) production than correction for a treatment specific blank. For instance, correcting carvacrol data using a blank without the additive resulted in negative net gas and CH(4) production (-6.5 and -1.5 ml. respectively). These biologically impossible results occurred because total gas and CH(4) production in blanks without carvacrol (46.1 and 2.1 ml, respectively) were higher than in flasks containing substrate plus carvacrol (39.7 and 0.6 ml, respectively). Results demonstrated that inclusion of rumen additives affected fermentation of OM in the substrate and the inoculum. Thus, correction of gas and CH(4) production using blanks without additives resulted in overestimation of these variables. Blanks containing the additive of interest should be included when rumen fermentation modifiers are evaluated in vitro. This paper is part of the special issue entitled: Greenhouse Gases in Animal Agriculture Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors: K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson. (C) 2011 Elsevier B.V. All rights reserved.

Green Chemistry-Sensitive Analytical Procedure for Photometric Determination of Orthophosphate in River and Tap Water by Use of a Simple LED-Based Photometer

In the current work a Green Analytical Chemistry (GAC) procedure for photometric determination of orthophosphate in river water at mu g L-1 concentration level is described. The flow system module and the LED-based photometer were assembled together to constitute a compact unit in order to allow that a flow cell with optical path-length of 100mm was coupled to them. The photometric procedure based on the molybdenum blue method was implemented employing the multicommuted flow injection analysis approach, which provided facilities to allow reduction of reagent consumption and as well as waste generation. Aiming to prove the usefulness of the system, orthophosphate in river and tap waters was determined. Accuracy was ascertained by spiking samples with orthophosphate solution yielding recoveries ranging from 96% up to 107%. Other profitable features such as a wide linear response range between 10 to 800 mu g L-1 [image omitted]; a detection limit (3 sigma criterion) of 2.4 mu g L-1 [image omitted]; a relative standard deviation (n=7) of 2% using a typical water sample with concentration of 120 mu g L-1 [image omitted]; reagent consumption of 3.0mg ammonium molybdate, 0.3mg hydrazine sulfate, and 0.03mg stannous chloride per determination; a waste generation of 2.4mL per determination; and a sampling throughput of 20 determination per hours were also achieved.

Evaluation of the use of multiple lines for determination of metals in water by inductively coupled plasma optical emission spectrometry with axial viewing

Inductively coupled plasma optical emission spectrometers (ICP DES) allow fast simultaneous measurements of several spectral lines for multiple elements. The combination of signal intensities of two or more emission lines for each element may bring such advantages as improvement of the precision, the minimization of systematic errors caused by spectral interferences and matrix effects. In this work, signal intensities for several spectral lines were combined for the determination of Al, Cd, Co, Cr, Mn, Pb, and Zn in water. Afterwards, parameters for evaluation of the calibration model were calculated to select the combination of emission lines leading to the best accuracy (lowest values of PRESS-Predicted error sum of squares and RMSEP-Root means square error of prediction). Limits of detection (LOD) obtained using multiple lines were 7.1, 0.5, 4.4, 0.042, 3.3, 28 and 6.7 mu g L(-1) (n = 10) for Al, Cd. Co, Cr, Mn, Pb and Zn, respectively, in the presence of concomitants. On the other hand, the LOD established for the most intense emission line were 16. 0.7, 8.4, 0.074. 23, 26 and 9.6 mu g L(-1) (n = 10) for these same elements in the presence of concomitants. The accuracy of the developed procedure was demonstrated using water certified reference material. The use of multiple lines improved the sensitivity making feasible the determination of these analytes according to the target values required for the current environmental legislation for water samples and it was also demonstrated that measurements in multiple lines can also be employed as a tool to verify the accuracy of an analytical procedure in ICP DES. (C) 2009 Elsevier B.V. All rights reserved.

Use of Medical Subject Headings (MeSH) in Portuguese for categorizing web-based healthcare content

Introduction: Internet users are increasingly using the worldwide web to search for information relating to their health. This situation makes it necessary to create specialized tools capable of supporting users in their searches. Objective: To apply and compare strategies that were developed to investigate the use of the Portuguese version of Medical Subject Headings (MeSH) for constructing an automated classifier for Brazilian Portuguese-language web-based content within or outside of the field of healthcare, focusing on the lay public. Methods: 3658 Brazilian web pages were used to train the classifier and 606 Brazilian web pages were used to validate it. The strategies proposed were constructed using content-based vector methods for text classification, such that Naive Bayes was used for the task of classifying vector patterns with characteristics obtained through the proposed strategies. Results: A strategy named InDeCS was developed specifically to adapt MeSH for the problem that was put forward. This approach achieved better accuracy for this pattern classification task (0.94 sensitivity, specificity and area under the ROC curve). Conclusions: Because of the significant results achieved by InDeCS, this tool has been successfully applied to the Brazilian healthcare search portal known as Busca Saude. Furthermore, it could be shown that MeSH presents important results when used for the task of classifying web-based content focusing on the lay public. It was also possible to show from this study that MeSH was able to map out mutable non-deterministic characteristics of the web. (c) 2010 Elsevier Inc. All rights reserved.

Cardiovascular response during trigeminal ganglion compression for trigeminal neuralgia according to the use of local anesthetics

There are controversies about the use of local anesthetics during balloon compression for trigeminal neuralgia (TN) as a protective factor for cardiovascular events. The objective of this study was to investigate cardiovascular parameters (blood pressure and heart rate [HR]) of patients that underwent trigeminal balloon compression with local anesthetics compared to a control group (placebo). This is a randomized controlled study; 55 patients were randomized into two groups: study (deep sedation and trigeminal block with 0.8-mL lidocaine 2%) and control group (deep sedation and trigeminal injection of 0.8-mL saline). Blood pressure and HR were measured in five distinct moments: preoperative, during puncture for local anesthesia/placebo, during puncture with the catheter, during balloon compression, and final evaluation. Statistical analysis was performed with Pearson`s chi (2) and McNemar tests and the analysis of variance for repetitive measures. The means of systolic and diastolic blood pressures (SBP and DBP, respectively) were higher in the control group when compared to the study group at the evaluation during puncture with the catheter (p < 0.001) and balloon compression (p < 0.001 and p = 0.018 for DBP and SBP, respectively). There was an increase in the HR in the control group during the procedure (p = 0.017). The use of local anesthetics during the trigeminal balloon compression for TN can have a preventive role for the risk of cardiovascular events.

The use of contingent valuation for evaluating protected areas in the developing world: Economic valuation of Morro do Diabo State Park, Atlantic Rainforest, Sao Paulo State (Brazil)

The Brazilian Atlantic Rainforest is internationally recognised as one of the most biodiverse and threatened tropical forests in the world [Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B., Kent, J., 2000. Biodiversity hotspots for conservation priorities. Nature 403, 853-858]. The Seasonal Semi-Deciduous Forest is among the most fragmented and threatened biomes of the Atlantic Rainforest Domain. The largest remnant of this biome (35,000 ha) is protected by the Morro do Diabo State Park (MDSP), situated in the area known as the Pontal do Paranapanema, in Sao Paulo State, Brazil. Despite its environmental importance, the park is under political, economic and demographic pressure. The main aim of our research was to estimate the population`s willingness to pay (WTP) for the conservation of MDSP and for the Atlantic Rainforest`s remnants in Sao Paulo State as a whole, by means of the contingent valuation method (CVM). The results featured a high incidence of null WTP and of protest votes. Nevertheless, the population is willing to pay US$ 2,113,548.00/year (R$ 7,080,385.00/year) for the conservation of the MDSP (use and existence values), or US$ 60.39 ha/year (R$ 202.30/ha/year). The results indicate that the preservation value is strongly associated to the population`s ability to pay, increasing with income levels. Qualitative research questions showed that the population considers protected areas to be very important. Still, the valuation of MDSP revealed a gap between the government budget allotted to the park and the value assigned to the area by the public. (C) 2007 Elsevier B.V. All rights reserved.

Use of Hyaluronidase to Prevent Perineal Trauma During Spontaneous Births: A Randomized, Placebo-Controlled, Double-blind, Clinical Trial

Introduction: The purpose of this study was to compare the frequency and severity of perineal trauma during spontaneous birth with or without perineal injections of hyaluronidase (HAase). Methods: A randomized, placebo-controlled, double-blind clinical trial was conducted in a midwife-led, in-hospital birth center in Sao Paulo, Brazil. Primiparous women (N = 160) were randomly assigned to an experimental (n = 80) or control (n = 80) group. During the second stage of labor, women in the experimental group received an injection of 20.000 turbidity-reducing units of HAase in the posterior region of the perineum, and those in the control group received a placebo injection. The assessment of perineal outcome was performed by 2 independent nurse-midwives. A 1-tailed Fisher exact test was performed, and a P value < .025 was considered statistically significant. Results: Perineal integrity occurred in 34.2% of the experimental group and in 32.5% of the control group, which was not a statistically significant difference (P = .477). First-degree laceration was the most common trauma in the posterior region of the perineum in women in both groups (experimental = 56%, control = 42.6%). Severe perineal trauma occurred in 28.9% of the experimental group and 38.8% of the control group, which also was not a statistically significant difference (P =. 131). The depth of second-degree perineal lacerations in the experimental and control groups, measured by the Peri-Rule, was 1.9 cm and 2.3 cm, respectively. An episiotomy was performed in 11 women (experimental group = 3, control group = 8), and 4 (all in control group) had third-degree lacerations. Discussion: The use of injectable HAase did not increase the proportion of intact perineum and did not reduce the proportion of severe perineal trauma in our sample. J Midwifery Womens Health 2011; 56: 436-445 (C) 2011 by the American College of Nurse-Midwives.

Use of hyaluronidase to prevent perineal trauma during spontaneous delivery: A pilot study

Our objective was to compare the frequency, degree, and location of perineal trauma during spontaneous delivery with or without perineal injections of hyaluronidase (HAase). This was a randomized, controlled pilot study, conducted in a midwifie-led hospital birth center in Sao Paulo, Brazil. Primiparous women (N = 139) were randomly assigned to an intervention group (HAase injection, n = 71) or to a control group (no injection, n = 68). Significant differences were noted between the two groups in frequency of perineal trauma (intervention, 39.4%; control, 76.5%), degree of spontaneous laceration (intervention, 0.0%; control, 82.4%), and laceration located in the posterior region of the perineum (intervention, 54.2%; control, 84.3%). When episiotomy and second-degree lacerations were considered together and women with intact perineum were excluded from the analysis, the difference between the groups was no longer significant. With the use of the HAase enzyme, the relative risk was 0.5 for perineal trauma and 0.0 for second-degree lacerations. The present findings suggest that perineal injection of HAase prevented perineal trauma. These findings provide strong rationale for a larger follow-up study.

Use of peripheral vision in the interception of moving targets

Use of peripheral vision to organize and reorganize an interceptive action was investigated in young adults. Temporal errors and kinematic variables were evaluated in the interception of a virtual moving target, in situations in which its initial velocity was kept unchanged or was unexpectedly decreased. Observation of target approach was made through continuous visual pursuit (focal vision) or keeping visual focus at the origin of the trajectory or at the contact spot (peripheral vision). Results showed that visual focus at the contact spot led to temporal errors similar to focal vision, although showing a distinct kinematic profile, while focus at the origin led to an impoverished performance

Use of activated charcoal and ion-exchange resin to cleaN up and concentrate enzymes in extracts from biodegraded wood.

Use of activated charcoal and ion-exchange resin to cleaN up and concentrate enzymes in extracts from biodegraded wood. Ceriporiopsis subvermispora was used for the biodegradation of Eucalyptus grandis chips in the presence or absence of co-substrates (glucose and corn steep liquor) during 7, 14 and 28 days. Afterwards, the biodegraded chips were extracted with 50 mM sodium acetate buffer (pH 5.5) supplemented with 0.01% Tween 60. High activities of manganese peroxidases (MnPs) were observed in all the extracts, both in the absence (430, 765 and 896 UI kg(-1) respectively) and in the presence of co-substrates (1,013; 2,066 and 2,323 UI kg(-1) respectively). The extracts presented a high ratio between absorbances at 280 and 405 nm, indicating a strong abundance of aromatic compounds derived from lignin over heme-peroxidases. Adsorption into activated charcoal showed to be an adequate strategy to reduce the absorbance at 280 urn in all the extracts. Moreover, it allowed to maximize the capacity of an anion exchange resin bed (DEAE-Sepharose) used to concentrate the MnPs present in the extracts. It was concluded that the use of activated charcoal followed by adsorption into DEAE Sepharose is a strategy that can be used to concentrate MnPs in extracts obtained during the biodegradation of E. grandis by C. subvermispora.