89 resultados para Quantificação
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
The scale is defined as chemical compounds from inorganic nature, initially soluble in salt solutions, which may precipitate accumulate in columns of production and surface equipment. This work aimd to quantify the crystalline phases of scale through the Rietveld method. The study was conducted in scale derived from columns production wells in development and recipients of pigs. After collecting samples of scale were performed the procedure for separations of inorganic and organic phase and preparation to be analyzed at the X-ray Laboratory. The XRD and XRF techniques were used to monitor whether identifying and quantifying crystalline phases present in the deposits. The SEM technique was used to visualize the morphology of the scales and assess their homogeneity after the milling process. XRD measurements were performed with and without milling and with or without the accessory spinner. For quantify crystalline phases the program DBWStools was used. The procedure for conducting the first refinement was instrumental in setting parameters, then the structural parameters of the phases in the sample and finally the parameters of the function profile used. In the diffraction patterns of samples of scale observed that the best measures were those that passed through the mill and used the accessory spinner. Through the results, it was noted that the quantitative analysis for samples of scale is feasible when need to monitor a particular crystalline phase in a well, pipeline or oil field. Routinely, the quantification of phases by the Rietveld method is hardwork because in many scale was very difficult to identify the crystalline phases present
Resumo:
Kalanchoe brasiliensis Cambess (Crassulaceae), commonly known as saião , coirama branca , folha grossa , is originally from Brazil and commonly found in São Paulo to Bahia, mainly in the coastal zone. Regarding of biological activities, most preclinical studies were found in the literature, mainly about the anti-inflammatory activity of extracts obtained from leaves and / or aerial parts of K. brasiliensis. As regards the chemical constitution, it has been reported mainly the presence of flavonoids in the leaves of the species, but until this moment did not knows which are the active compounds. Although it is a species widely used in traditional medicine in Brazil, there is no monograph about the quality parameters of the plant drug. In this context, this study aims to characterize and quantify the chemical markers of hydroethanolic extract (HE) from the leaves of K. brasiliensis, which can be used in quality control of plant drug and derivatives obtained from this species. The methodology was divided into two parts: i. Phytochemical study: to fractionate, isolate and characterizate of the chemical (s) marker (s) of the HE from the leaves of K. brasiliensis; ii. To Developed validate of analytical method by High Performance Liquid Chromatography (HPLC)-diode array detector (DAD) to quantify the chemical (s) marker (s) of the EH. i. The EH 50% was prepared by turbo extraction method. It was then submitted to liquid-liquid partition, obtaining dichloromethane, n-butanol and ethyl acetate (AcOEt) fractions. The AcOEt fraction was selected to continue the fractionation process, because it has a chemical profile rich in flavonoids. The acOEt fraction was submitted to column chromatography using different systems for obtaining the compound Kb1. To identify this compound, it was submitted to UV analysis ii. For quantitative analysis, the EH was analyzed by HPLC, using different methods. After selecting the most appropriate method, which showed satisfactory resolution and symmetrical peaks, it was validated according to parameters in the RE 899/2003. As result, it was obtained from the AcOEt fraction the compound Kb1 (2.7 mg). Until this moment, the basic nucleus was characterized by UV analysis using shift reagents. The partial chemical structure of the compound Kb1 was identified as a flavonol, containing hydroxyls in 3 , 4 position (ring A), 5 and 7 free (ring B) and a replacement of the C3 hydroxyl by a sugar. As the analysis were performed in the HPLC coupled to a DAD, we observed that the UV spectrum of the major peaks of EH from K. brasiliensis shown similar UV spectrum. According to the literature, it has been reported the presence of patuletin glycosydes derivatives in the leaves of this species. Therefore, it is suggested that the compound Kb1 is glycosylated patuletin derivative. Probably the sugar (s) unit(s) are linked in the C3 in the C ring. . Regarding the development of HPLC analytical method, the system used consists of phase A: water: formic acid (99,7:0,3, v / v) and phase B: methanol: formic acid (99,7:0,3, v / v), elution gradient of 40% B - 58% B in 50 minutes, ccolumn (Hichrom ®) C18 (250x4, 0 mm, 5 μm), flow rate 0.8 mL / min, UV detection at 370 nm, temperature 25 ° C. In the analysis performed with the co-injection of thecompound Kb1 + HE of K. brasiliensis was observed that it is one of the major compounds with a retention time of 12.47 minutes and had a content of 15.3% in EH of leaves from K. brasiliensis. The method proved to be linear, precise, accurate and reproducible. According to these results, it was observed that compound Kb1 can be used as a chemical marker of EH from leaves of K. brasiliensis, to assist in quality control of drug plant and its derivatives
Resumo:
The strengthening of the domestic industry in Brazil required the modernization, mechanization and expansion of salt production. Thereafter the production of sea salt started to be made in a process of continuous flow, where the product is constantly stored in yards, with daily movements in and out of salt. Thus far, the major bottleneck found in this production process is the control of production, because due to the large amount produced and variety of losses existing in the various stages of production there are not a regulated and safe way to control inventories with accuracy and speed demanded. In a typical case with a salt marsh company of Rio Grande do Norte state, salt produced is stored in two open courtyards and inventory control of salt made by carrying input / output relationship of salt in each storage yard. This work developed a conceptual model of inventory control, based on topography, adopting surveys into one of the courtyards of the company. There were 25 biweekly survey measurements over a year book to generate digital models representing the stock. For each measurement, results were compared with the values of inventory accounting provided by the salt marsh in order to identify existing losses and mark out the sales department on the actual stock available at each measurement date. Inventories calculated by the model indicated losses of 6,349 tonnes for the period of one year book and 3,279 tonnes for the period between harvests, when compared to the accounting control
Resumo:
This dissertation aims the development of an experimental device to determine quantitatively the content of benzene, toluene and xylenes (BTX) in the atmosphere. BTX are extremely volatile solvents, and therefore play an important role in atmospheric chemistry, being precursors in the tropospheric ozone formation. In this work a BTX new standard gas was produced in nitrogen for stagnant systems. The aim of this dissertation is to develop a new method, simple and cheaper, to quantify and monitor BTX in air using solid phase microextraction/ gas chromatography/mass spectrometry (SPME/CG/MS). The features of the calibration method proposed are presented in this dissertation. SPME sampling was carried out under non-equilibrium conditions using a Carboxen/PDMS fiber exposed for 10 min standard gas mixtures. It is observed that the main parameters that affect the extraction process are sampling time and concentration. The results of the BTX multicomponent system studied have shown a linear and a nonlinear range. In the non-linear range, it is remarkable the effect of competition by selective adsorption with the following affinity order p-xylene > toluene > benzene. This behavior represents a limitation of the method, however being in accordance with the literature. Furthermore, this behavior does not prevent the application of the technique out of the non-linear region to quantify the BTX contents in the atmosphere.
Resumo:
PAHs (Polycyclic Aromatic Hydrocarbons) are a group of organic substances which receive considerable attention because of the carcinogenic and mutagenic properties of some of them. It is therefore important to determine the PAHs in different environmental matrices. Several studies have shown the use of gas chromatography coupled to mass spectrometry as a technique for quantification of PAHs by presenting excellent detection limits. This study aimed to develop an analytical methodology for the determination of 16 PAHs listed by the USEPA, test two methods for extraction of PAHs in water from a 23 factorial design, quantify them through the analytical technique coupled to gas chromatography mass spectrometry (GC/MS) using the method developed, and finally apply the results in chemometrics. The sample was synthesized and subjected to tests of the 23 factorial design, which has the factors: the type of extraction technique (ultrasound and digester), the ratio solvent / sample (1:1 and 1:3) and the type of solvent (dichloromethane / hexane and acetone / dichloromethane). The responses of eight combinations of the factorial design were obtained from the quantification by external calibration in GC/MS. The quantification method was developed from an optimized adaptation of the USEPA Method 8270. We used the full scan mode as a way of acquiring the mass spectra of 16 PAHs. The time in which the samples were subjected to ultrasound was fixed at 10 min and held an investigation to establish the conditions of power and time in the digester. We had the best response in the investigation of the digester power of 100 watts and the time of six minutes. The factorial design of liquid-liquid extraction showed that the most representative factors were: the use of the digester as extraction technique, the ratio solvent / sample 1:1 and the use of a 1:1 mixture of dichloromethane / hexane as a solvent more suitable. These results showed that the 1:1 mixture of dichloromethane / hexane is an excellent mixture to recover the extraction of PAHs an aqueous sample using the microwave digester. The optimization of the method of separation, identification and quantification of PAHs in the GC/MS was valid for 16 PAHs present in each chromatogram of the samples
Resumo:
In this work we used chemometric tools to classify and quantify the protein content in samples of milk powder. We applied the NIR diffuse reflectance spectroscopy combined with multivariate techniques. First, we carried out an exploratory method of samples by principal component analysis (PCA), then the classification of independent modeling of class analogy (SIMCA). Thus it became possible to classify the samples that were grouped by similarities in their composition. Finally, the techniques of partial least squares regression (PLS) and principal components regression (PCR) allowed the quantification of protein content in samples of milk powder, compared with the Kjeldahl reference method. A total of 53 samples of milk powder sold in the metropolitan areas of Natal, Salvador and Rio de Janeiro were acquired for analysis, in which after pre-treatment data, there were four models, which were employed for classification and quantification of samples. The methods employed after being assessed and validated showed good performance, good accuracy and reliability of the results, showing that the NIR technique can be a non invasive technique, since it produces no waste and saves time in analyzing the samples
Resumo:
The development of more selective and sensitive analytical methods is of great importance in different areas of knowledge, covering, for example, food, biotechnological, environmental and pharmaceutical sectors. The study aimed to employ the technique electroanalytical differential pulse voltammetry (DPV) as an innovative and promising alternative for identification and quantification of organic compounds. The organic compounds were investigated in this study oxalic acid (OA) and folic acid (FA). The electrochemical oxidation of oxalic acid has been extensively studied as a model reaction in the boundary between the organic and inorganic electrochemistry. Since the AF, an essential vitamin for cell multiplication in all tissues, which is essential for DNA synthesis. The AF has been investigated using analytical techniques, liquid chromatography and molecular absorption spectrophotometry. The results obtained during the experimental procedure indicated that the process of electrochemical oxidation of oxalic acid is strongly dependent on the nature of the anode material and the oxidation mechanism, which affects their detection. Efficient removal was observed in Ti/PbO2 anodes, graphite, BDD and Pt 90, 85, 80 and 78% respectively. It was also shown that the DPV employing glassy carbon electrode offers a fast, simple, reliable and economical way to determine the AO during the process of electrochemical oxidation. Furthermore, electroanalytical methods are more expensive than commonly used chromatographic analysis and other instrumental methods involving toxic reagents and higher cost. Compared with the classical method of titration and DPV could be a good fit, confidence intervals and detection limits confirming the applicability of electroanalytical technique for monitoring the degradation of oxalic acid. For the study of AF was investigated the electrocatalytic activity of the carbon paste electrode for identification and quantification in pharmaceutical formulations by applying the DPV. The results obtained during the experimental procedure showed an irreversible oxidation peak at 9.1 V characteristic of FA. The carbon paste sensor showed low detection limit of 5.683×10−8 mol L-1 reducing matrix effects. The spectrophotometric analysis showed lower concentrations of HF compared with those obtained by HPLC and DPV. The levels of AF were obtained according to the methodology proposed by the Brazilian Pharmacopoeia. The electroanalytical method (DPV) proposed is cheaper than GC analysis commonly used by the pharmaceutical industry. The results demonstrated the potential of these electroanalytical techniques for future applications in environmental, chemical and biological sensors
Resumo:
This thesis was performed in four chapters, at the theoretical level, focused mainly on electronic density. In the first chapter, we have applied an undergraduate minicourse of Diels-Alder reaction in Federal University of Rio Grande do Norte. By using computational chemistry tools students could build the knowledge by themselves and they could associate important aspects of physical-chemistry with Organic Chemistry. In the second chapter, we studied a new type of chemical bond between a pair of identical or similar hydrogen atoms that are close to electrical neutrality, known as hydrogen-hydrogen (H-H) bond. In this study performed with complexed alkanes, provides new and important information about their stability involving this type of interaction. We show that the H-H bond playing a secondary role in the stability of branched alkanes in comparison with linear or less branched isomers. In the third chapter, we study the electronic structure and the stability of tetrahedrane, substituted tetrahedranes and silicon and germanium parents, it was evaluated the substituent effect on the carbon cage in the tetrahedrane derivatives and the results indicate that stronger electron withdrawing groups (EWG) makes the tetrahedrane cage slightly unstable while slight EWG causes a greater instability in the tetrahedrane cage. We showed that the sigma aromaticity EWG and electron donating groups (EDG) results in decrease and increase, respectively, of NICS and D3BIA aromaticity indices. In addition, another factor can be utilized to explain the stability of tetra-tert-butyltetrahedrane as well as HH bond. GVB and ADMP were also used to explain the stability effect of the substituents bonded to the carbon of the tetrahedrane cage. In the fourth chapter, we performed a theoretical investigation of the inhibitory effect of the drug abiraterone (ABE), used in the prostate cancer treatment as CYP17 inhibitor, comparing the interaction energies and electron density of the ABE with the natural substrate, pregnenolone (PREG). Molecular dynamics and docking were used to obtain the CYP1ABE and CYP17-PREG complexes. From molecular dynamics was obtained that the ABE has higher diffusion trend water CYP17 binding site compared to the PREG. With the ONIOM (B3LYP:AMBER) method, we find that the interaction electronic energy of ABE is 21.38 kcal mol-1 more stable than PREG. The results obtained by QTAIM indicate that such stability is due a higher electronic density of interactions between ABE and CYP17
Resumo:
The Benzylpenicillin (PENG) have been as the active ingredient in veterinary medicinal products, to increase productivity, due to its therapeutic properties. However, one of unfortunate quality and used indiscriminately, resulting in residues in foods exposed to human consumption, especially in milk that is essential to the diet of children and the ageing. Thus, it is indispensable to develop new methods able to detect this waste food, at levels that are toxic to human health, in order to contribute to the food security of consumers and collaborate with regulatory agencies in an efficient inspection. In this work, were developed methods for the quality control of veterinary drugs based on Benzylpenicillin (PENG) that are used in livestock production. Additionally, were validated methodologies for identifying and quantifying the antibiotic residues in milk bovine and caprine. For this, the analytical control was performed two steps. At first, the groups of samples of medicinal products I, II, III, IV and V, individually, were characterized by medium infrared spectroscopy (4000 – 600 cm-1). Besides, 37 samples, distributed in these groups, were analyzed by spectroscopy in the ultraviolet and near infrared region (UV VIS NIR) and Ultra Fast Liquid Chromatograph coupled to linear arrangement photodiodes (UFLC-DAD). The results of the characterization indicated similarities, between PENG and reference standard samples, primarily in regions of 1818 to 1724 cm-1 of ν C=O that shows primary amides features of PENG. The method by UFLC-DAD presented R on 0.9991. LOD of 7.384 × 10-4 μg mL-1. LOQ of 2.049 × 10-3 μg mL-1. The analysis shows that 62.16% the samples presented purity ≥ 81.21%. The method by spectroscopy in the UV VIS NIR presented medium error ≤ 8 – 12% between the reference and experimental criteria, indicating is a secure choice for rapid determination of PENG. In the second stage, was acquiring a method for the extraction and isolation of PENG by the addition of buffer McIlvaine, used for precipitation of proteins total, at pH 4.0. The results showed excellent recovery values PENG, being close to 92.05% of samples of bovine milk (method 1). While samples of milk goats (method 2) the recovery of PENG were 95.83%. The methods for UFLC-DAD have been validated in accordance with the maximum residue limit (LMR) of 4 μg Kg-1 standardized by CAC/GL16. Validation of the method 1 indicated R by 0.9975. LOD of 7.246 × 10-4 μg mL-1. LOQ de 2.196 × 10-3 μg mL-1. The application of the method 1 showed that 12% the samples presented concentration of residues of PENG > LMR. The method 2 indicated R by 0.9995. LOD 8.251 × 10-4 μg mL-1. LOQ de 2.5270 × 10-3 μg mL-1. The application of the method showed that 15% of the samples were above the tolerable. The comparative analysis between the methods pointed better validation for LCP samples, because the reduction of the matrix effect, on this account the tcalculs < ttable, caused by the increase of recovery of the PENG. In this mode, all the operations developed to deliver simplicity, speed, selectivity, reduced analysis time and reagent use and toxic solvents, particularly if compared to the established methodologies.
Resumo:
The Benzylpenicillin (PENG) have been as the active ingredient in veterinary medicinal products, to increase productivity, due to its therapeutic properties. However, one of unfortunate quality and used indiscriminately, resulting in residues in foods exposed to human consumption, especially in milk that is essential to the diet of children and the ageing. Thus, it is indispensable to develop new methods able to detect this waste food, at levels that are toxic to human health, in order to contribute to the food security of consumers and collaborate with regulatory agencies in an efficient inspection. In this work, were developed methods for the quality control of veterinary drugs based on Benzylpenicillin (PENG) that are used in livestock production. Additionally, were validated methodologies for identifying and quantifying the antibiotic residues in milk bovine and caprine. For this, the analytical control was performed two steps. At first, the groups of samples of medicinal products I, II, III, IV and V, individually, were characterized by medium infrared spectroscopy (4000 – 600 cm-1). Besides, 37 samples, distributed in these groups, were analyzed by spectroscopy in the ultraviolet and near infrared region (UV VIS NIR) and Ultra Fast Liquid Chromatograph coupled to linear arrangement photodiodes (UFLC-DAD). The results of the characterization indicated similarities, between PENG and reference standard samples, primarily in regions of 1818 to 1724 cm-1 of ν C=O that shows primary amides features of PENG. The method by UFLC-DAD presented R on 0.9991. LOD of 7.384 × 10-4 μg mL-1. LOQ of 2.049 × 10-3 μg mL-1. The analysis shows that 62.16% the samples presented purity ≥ 81.21%. The method by spectroscopy in the UV VIS NIR presented medium error ≤ 8 – 12% between the reference and experimental criteria, indicating is a secure choice for rapid determination of PENG. In the second stage, was acquiring a method for the extraction and isolation of PENG by the addition of buffer McIlvaine, used for precipitation of proteins total, at pH 4.0. The results showed excellent recovery values PENG, being close to 92.05% of samples of bovine milk (method 1). While samples of milk goats (method 2) the recovery of PENG were 95.83%. The methods for UFLC-DAD have been validated in accordance with the maximum residue limit (LMR) of 4 μg Kg-1 standardized by CAC/GL16. Validation of the method 1 indicated R by 0.9975. LOD of 7.246 × 10-4 μg mL-1. LOQ de 2.196 × 10-3 μg mL-1. The application of the method 1 showed that 12% the samples presented concentration of residues of PENG > LMR. The method 2 indicated R by 0.9995. LOD 8.251 × 10-4 μg mL-1. LOQ de 2.5270 × 10-3 μg mL-1. The application of the method showed that 15% of the samples were above the tolerable. The comparative analysis between the methods pointed better validation for LCP samples, because the reduction of the matrix effect, on this account the tcalculs < ttable, caused by the increase of recovery of the PENG. In this mode, all the operations developed to deliver simplicity, speed, selectivity, reduced analysis time and reagent use and toxic solvents, particularly if compared to the established methodologies.
Resumo:
The scale is defined as chemical compounds from inorganic nature, initially soluble in salt solutions, which may precipitate accumulate in columns of production and surface equipment. This work aimd to quantify the crystalline phases of scale through the Rietveld method. The study was conducted in scale derived from columns production wells in development and recipients of pigs. After collecting samples of scale were performed the procedure for separations of inorganic and organic phase and preparation to be analyzed at the X-ray Laboratory. The XRD and XRF techniques were used to monitor whether identifying and quantifying crystalline phases present in the deposits. The SEM technique was used to visualize the morphology of the scales and assess their homogeneity after the milling process. XRD measurements were performed with and without milling and with or without the accessory spinner. For quantify crystalline phases the program DBWStools was used. The procedure for conducting the first refinement was instrumental in setting parameters, then the structural parameters of the phases in the sample and finally the parameters of the function profile used. In the diffraction patterns of samples of scale observed that the best measures were those that passed through the mill and used the accessory spinner. Through the results, it was noted that the quantitative analysis for samples of scale is feasible when need to monitor a particular crystalline phase in a well, pipeline or oil field. Routinely, the quantification of phases by the Rietveld method is hardwork because in many scale was very difficult to identify the crystalline phases present
Resumo:
VANTI, Nadia. Links hipertextuais na comunicação científica: análise webométrica dos sítios acadêmicos latino-americanos em Ciências Sociais. Porto Alegre, 2007. 292 f. Tese (Doutorado em Comunicação e Informação) – Universidade Federal do Rio Grande do Sul. Porto Alegre, 2007.
Resumo:
Os fatores de crescimento são substâncias moduladoras do processo de cicatrização. O fator de crescimento de fibroblastos básico (FCFß) liberado pelas plaquetas, macrófagos e pelos próprios fibroblastos, estimulam a proliferação celular, a produção de colágeno e de outros elementos da matriz celular, favorecendo o processo da cicatrização, mesmo em situações adversas, como diabetes e uso de corticosteróides. O presente estudo objetivou determinar a influência do FCFb no processo de cicatrização de anastomoses esofageanas em modelo de experimentação animal, avaliando-se a resistência à pressão,formação de tecido de granulação e deposição de colágeno. Método: Foram estudados dois grupos A e B,ambos com 10 ratos de linhagem Wistar, separados de forma aleatória, todos submetidos à secção e anastomose do esôfago por via abdominal. Nos animais do grupo A, foi feita aplicação tópica na linha de sutura de 10ng de FCFb. No grupo B (controle) foi aplicado igual volume de solução salina. Os animais foram sacrificados no 7º dia, o esôfago ressecado para teste de resistência da anastomose, estudo qualitativo do aporte de células inflamatórias, da angiogênese e quantificação do colágeno na zona da anastomose, através de sistema digital. Resultados: A densidade média dos parâmetros histológicos do grupo A foi 9095,51±1284,5, maior que no grupo B, que teve densidade 7162,4±1273,19 (p=0,013). A resistência da anastomose do grupo A teve a média 210±18,88 mmHg, significativamente maior que no grupo B, que atingiu o valor 157±29,55 mmHg (p=0,0024). Conclusão: Este estudo concluiu que o FCFß atuou melhorando a cicatrização e aumentando significativamente a resistência de anastomoses do esôfago realizadas em ratos
Resumo:
Objetivo: Trabalho realizado em ratos com o objetivo de estudar o efeito do Fator de Crescimento de Fibroblastos básico (FCFb) na cicatrização da aponeurose abdominal. Métodos: Foram usados 20 ratos Wistar separados aleatoriamente em 2 grupos iguais. Os animais foram anestesiados com pentobarbital sódico na dose de 20 mg/Kg por via intraperitoneal e submetidos a laparotomia mediana de 4 cm, cuja camada aponeurótica foi suturada com mononylon 5-0. No grupo I foi aplicada a dose de 5mg de FCFb sobre a sutura da aponeurose. No grupo II (controle) foi aplicada solução salina 0,9% sobre a linha se sutura. Após observação por 7 dias os animais foram mortos com superdose de anestésico. A camada aponeurótica com 1,5 cm de largura foi submetida a teste de resistência à tensão empregando a Máquina de Ensaios EMIC MF500. Biópsias das zonas de sutura foram processadas e coradas com HE e o tricômico de Masson. Os achados histopatológicos foram quantificados através de sistema digital (Image pro-plus) de captura e processamento de imagens. Os dados obtidos foram analisados pelo teste T com significância 0,05. Resultados: Nos animais do grupo I (experimental) a zona de sutura da camada aponeurótica suportou a carga de 1.103±103,39gf. A quantificação dos dados histopatológicos desse grupo atingiu a densidade média 226±29,32. No grupo II (controle) a carga suportada pela zona de sutura foi de 791,1±92,77 gf. Quando foram comparadas as médias das resistências à tensão dos dois grupos, observou-se uma diferença significante (p<0,01). O exame histopatológico das lâminas desse grupo relevou densidade média 114,1±17,01, correspondendo a uma diferença significante quando comparadas as médias dos dois grupos (p<0,01). Conclusão: Os dados permitem concluir que o FCFb contribuiu para aumentar a resistência da aponeurose suturada e para melhorar os parâmetros histopatológicos da cicatrização.
Resumo:
Para avaliar os efeitos de diferentes tempos de pré-condicionamento isquêmico (IPC) em translocação bacteriana intestinal (BT). MÉTODOS: Trinta ratos Wistar pesando 280 ± 27g foram divididos em cinco grupos. No grupo IV (n = 6), a laparotomia foi realizada e a artéria mesentérica superior foi obstruído por um microclampe atraumática durante 30 minutos. Nos quatro grupos de pré-condicionamento (n = 6 cada) antes dos 30 minutos de isquemia-reperfusão (I / R), os ratos foram submetidos a IPC para duas, cinco, dez e 15 minutos, seguido pelo mesmo momento da reperfusão. A fim de avaliar se o tempo de pré-condicionamento influenciaram o surgimento de translocação bacteriana, as amostras de nódulos linfáticos mesentéricos, fígado e baço foram colhidas em condições estéreis, 24 horas após os procedimentos para a quantificação de unidades formadoras de colónias de bactérias por grama de tecido (CFU / g). O sangue foi recolhido para a medição de citoquinas. RESULTADOS: No grupo I / R, o total de CFU / g em gânglios linfáticos mesentéricos, baço, fígado, bem como o soro de TNF-a, IL-1A e IL-6 foram significativamente mais elevados do que nos outros grupos (p <0,05). Pré-condicionamento por 15 minutos significativamente atenuada BT e citocinas séricas quando comparado a outros períodos de pré-condicionamento (p <0,05). CONCLUSÃO: Nossos dados sugerem que o pré-condicionamento como um fator chave para reduzir a translocação bacteriana intestinal em I / R. Numa escala de dois a 15 minutos, o melhor tempo de pré-condicionamento isquémico pela atenuação da translocação bacteriana foi de 15 minutos