Swine Pancreas Research Articles

Comparative efficacies and safeties of cylindrical interstitial laser ablation and radiofrequency ablation on swine pancreas.

Laser ablation (LA) has been evaluated for the minimally invasive thermal treatment of various cancers, but conventional unidirectional endoscopic ultrasound (EUS)-guided LA has limitations. Therefore, we developed a cylindrical laser diffuser to overcome the limitations of unidirectional EUS-guided LA. The purpose of this study was to compare the efficacies and safeties of EUS-guided LA using a novel cylindrical laser diffuser and radiofrequency ablation (RFA) in vivo in swine pancreas. EUS-guided RFA (15 W, 30s, 450J) and cylindrical interstitial LA (CILA) (5 W, 90s, 450J) were applied to normal pancreatic tissue in six anesthetized pigs (three per group). Laboratory tests were performed at baseline, immediately after ablation (day 0), and 2days after procedures (day 2). Two days after procedures, all pigs were sacrificed, and histopathological safety and efficacy assessments were performed. Technically, EUS-guided RFA and CILA were performed successfully in all cases. No major complications, including perforation or acute pancreatitis, occurred during the experiment in either group. All animals remained in excellent condition throughout the experimental period, and laboratory tests provided no evidence of a major complication. Average necrotic volumes in the RFA and CILA groups were 424.2 mm3 and 3747.4 mm3, respectively, and average necrotic volume was significantly larger in CILA group (p < 0.001). EUS-guided RFA and CILA had acceptable safety profiles in the normal swine pancreas model. Our findings indicate EUS-guided CILA has potential for the effective local treatment of pancreatic cancer as an alternative to EUS-guided RFA.

Normothermic Ex Vivo Pancreas Perfusion for the Preservation of Pancreas Allografts before Transplantation.

Pancreas transplantation (PTx) is a curative treatment for people who live with the burden of a diagnosis of diabetes mellitus (DM). However, due to organ shortages and increasing numbers of patients being listed for PTx, new strategies are needed to increase the number of available grafts for transplantation. Static cold storage (SCS) is considered the gold standard for standard criteria organs. However, standard criteria donors (SCD) are becoming scarce and new strategies that can increase the rate of organ acceptance from extended criteria donors (ECD) are urgently needed. Normothermic ex vivo perfusion (NEVP) is one of the strategies that has become increasingly popular over the past couple of decades. This preservation method has already been used successfully in other organs (liver, kidneys, and lungs) but has been minimally explored in pancreas transplantation. The few papers that describe the method for pancreas show little success, edema being one of the major issues. The following manuscript describes the successful NEVP method and setup developed by our group to perfuse swine pancreas.

1.5-Dimensional Circular Array Transducer for In Vivo Endoscopic Ultrasonography.

Traditional endoscopic ultrasonography (EUS), which uses one-dimensional (1-D) curvilinear or radial/circular transducers, cannot achieve dynamic elevational focusing, and the slice thickness is not sufficient. The purpose of this study was to design and fabricate a 1.5-dimensional (1.5-D) circular array transducer to achieve dynamic elevational focusing in EUS in vivo. An 84 × 5 element 1.5-D circular array transducer was successfully developed and characterized in this study. It was fabricated with PZT-5H 1-3 composite that attained a high-electromechanical coupling factor and low-acoustic impedance. The acoustic field distribution was measured with different transmission modes to validate the 1.5-D elevational beam focusing capability. The imaging performance of the 84 × 5 element 1.5-D circular array transducer was evaluated by two wire phantoms, an agar-based cyst phantom, an ex vivo swine pancreas, and an in vivo rhesus macaque rectum based on multifocal ray-line imaging method with five-row elevational beam steering. It was demonstrated that the transducer exhibited a central frequency of 6.47 MHz with an average bandwidth of 50%, a two-way insertion loss of 23 dB, and crosstalk of <-26 dB around the center frequency. Dynamic elevational focusing and the enhancement of the slice thickness in EUS were obtained with a 1.5-D circular array transducer. This study promotes the development of multirow and two-dimensional array EUS probes for a more precise clinical diagnosis and treatment.

A novel reaction force-fluorescence measurement system for evaluating pancreatic juice leakage from an excised swine pancreas during distal pancreatectomy.

Resection using a stapler is a popular approach to distal pancreatectomy. However, the resulting leakage of pancreatic juice represents a serious problem. We have developed a force-fluorescence measurement as a first step towards the quantitative evaluation of pancreatic leakage due to tissue tearing under compression. The system comprises a testing machine with an indenter, similar in size to a stapler, which controls compression speed and measures reaction force, and a fluorescence measurement system to measure pancreatic juice leakage. Pancreatic juice leakage is measured as the maximum value of the increasing rate of fluorescence intensity (max value). Ten excised swine pancreases were compressed at a speed of 500, 100, and 10mm/min until their thicknesses became 2mm. A strong positive correlation (0.804) was observed between the increase in max value before and after compression and the amount of reaction force drop due to tissue destruction. No pancreatic juice leakage was observed when compressed slowly (10mm/min). We have successfully developed a novel force-fluorescence measurement system that can detect and quantify pancreatic juice leakage caused by tissue tearing. This system can determine the optimal compression conditions for preventing pancreatic juice leakage.

Experimental High-Frequency Irreversible Electroporation Using a Single-Needle Delivery Approach for Nonthermal Pancreatic Ablation In Vivo

PurposeTo investigate the feasibility of single-needle high-frequency irreversible electroporation (SN-HFIRE) to create reproducible tissue ablations in an in vivo pancreatic swine model. Materials and MethodsSN-HFIRE was performed in swine pancreas in vivo in the absence of intraoperative paralytics or cardiac synchronization using 3 different voltage waveforms (1-5-1, 2-5-2, and 5-5-5 [on-off-on times (μs)], n = 6/setting) with a total energized time of 100 μs per burst. At necropsy, ablation size/shape was determined. Immunohistochemistry was performed to quantify apoptosis using an anticleaved caspase-3 antibody. A numerical model was developed to determine lethal thresholds for each waveform in pancreas. ResultsMean tissue ablation time was 5.0 ± 0.2 minutes, and no cardiac abnormalities or muscle twitch was detected. Mean ablation area significantly increased with increasing pulse width (41.0 ± 5.1 mm2 [range 32–66 mm2] vs 44 ± 2.1 mm2 [range 38–56 mm2] vs 85.0 ± 7.0 mm2 [range 63–155 mm2]; 1-5-1, 2-5-2, 5-5-5, respectively; p < 0.0002 5-5-5 vs 1-5-1 and 2-5-2). The majority of the ablation zone did not stain positive for cleaved caspase-3 (6.1 ± 2.8% [range 1.8–9.1%], 8.8 ± 1.3% [range 5.5–14.0%], and 11.0 ± 1.4% [range 7.1–14.2%] cleaved caspase-3 positive 1-5-1, 2-5-2, 5-5-5, respectively), with significantly more positive staining at the 5-5-5 pulse setting compared with 1-5-1 (p < 0.03). Numerical modeling determined a lethal threshold of 1114 ± 123 V/cm (1-5-1 waveform), 1039 ± 103 V/cm (2-5-2 waveform), and 693 ± 81 V/cm (5-5-5 waveform). ConclusionsSN-HFIRE induces rapid, predictable ablations in pancreatic tissue in vivo without the need for intraoperative paralytics or cardiac synchronization.

Experimental study in vivo ablation of swine pancreas using high-intensity focused ultrasound.

The objective of this study is to evaluate the feasibility and safety of high-intensity focused ultrasound (HIFU) for ablation of swine pancreas and to detect the pathological variations in pancreas damage. (a) Eight swine were involved and randomly divided into two groups (Group A and B). HIFU was applied on swine in both groups for in vivo ablation of pancreas. The animals were anesthetized, and the artificial acoustic window was built. Then, the irradiation of FEP-BY02 type HIFU on pancreas was applied. (b) Swine in Group A were euthanized immediately after treating with HIFU to examine variations in pancreas. The biochemical evidence of pancreatitis was evaluated by blood samples collected from swine in Group B before and after HIFU. Then, the pancreas of swine in Group B was euthanized on day 5 after treatment to examine the pancreas. All specimens were visually inspected for both ultrasonic focal damage region (UFDR) and pathological routine by a skilled pathologist. (a) The vital signs of all animals were stable during HIFU treatment and recovered well after treatment. (b) UFDR were observed in all HIFU irradiation region of the specimens, without significant size difference between the two groups. The coagulation nucleus pyknosis, cytochylema vacuolation, and nucleus membrane disruption were observed after HIFU in both groups. Membranous structure dissolution and inflammatory cell infiltration were also found after HIFU in swine of Group B. (c) There was no significant difference in the levels of blood amylase in swine of Group B before and after HIFU treatment. It was feasible and safe to use HIFU for ablation of the pancreas in swine.

High velocity pulse biopsy device enables controllable and precise needle insertion and high yield tissue acquisition

Minimally invasive biopsies are a cornerstone of breast cancer management with ultrasound being the preferred guidance modality. New developments in breast cancer management and advances in imaging technologies bring new challenges to current biopsy methodologies. A new biopsy device (NeoNavia® biopsy system, 14 G) was developed. It incorporates a pneumatic needle insertion mechanism that is intended to provide better control of needle progression and enable stepwise insertion without noticeable deformation or displacement of surrounding tissue as visualized under ultrasound. A new method of tissue acquisition was designed to achieve a sampling yield higher than standard methodologies. Needle dynamics was assessed on a specifically designed test bed and sampling performance was compared to a Magnum® biopsy instrument (Bard, Covington, GA, USA) in representative tissue models. The histological quality of samples obtained ex-vivo was evaluated. A pneumatic pulse was measured to accelerate the needle to a maximum velocity of 21.2 ± 2.5 m/s on a stroke length of 2.5 mm, achieving significantly higher acceleration, maximum velocity and power than current biopsy devices. Mean weight of samples obtained by the NeoNavia device were 3.5, 4.6, and 4.3 times higher when sampling was performed in turkey breast, calf thymus and swine pancreas, respectively, as compared to samples obtained with the Magnum instrument. Ex-vivo analysis indicates that the method of tissue acquisition has no apparent negative impact on the histopathologic quality of obtained samples.

Hydrogen sulfide enhances pancreatic β-cell differentiation from human tooth under normal and glucotoxic conditions.

Glucotoxicity obstructs pancreatic differentiation from adult stem cells. The aim was to develop a novel protocol for differentiation of dental pulp stem cells (DPSCs) into pancreatic β cells and determine the effect of H2S on glucotoxicity. DPSCs were differentiated with media containing 5.5 or 25.0 mM glucose, exposed to 1 ng/ml H2S. Glucotoxicity, expression of β-cell markers, INS, PDX1 and GLUT2, and PI3K/AKT pathway were assessed. H2S exposure increased insulin and C-peptide, and protected DPSC-derived pancreatic β-like cells from glucotoxicity and upregulated INS, PDX1 and GLUT2, and genes of PI3K/AKT pathway. H2S improved effects of glucotoxicity on β-like cells via PI3K/AKT pathway. The protocol for pancreatic β-cell differentiation might have applications in regenerative medicine rather than swine pancreas transplantation.

Goniometric measurement for the estimation of anisotropy coefficient of human and animal pancreas.

Estimation of optical properties of biologic tissues is determinant for laser dosimetry in medical applications. Tissues highly absorb and scatter the light in near infrared spectrum, where the laser provides therapeutic effects. Novel frontiers of clinical practice, e.g., the employment of laser light for the treatment of pancreatic cancer, require information about pancreas-laser interaction, which are crucial for therapy management. The property of biological tissues to scatter the light traveling through is described by the anisotropy coefficient (g). The relationship between g and the angular distribution of the scattered light is described by Henyey-Greenstein phase function. The measurement of angular distribution of scattered light is performed by the goniometric technique. This paper describes the estimation of g of ex vivo pancreas at 1064 nm, performed by a goniometric-based system, where a photodetector measures intensities of scattered light at fixed angles between -120° and 120°. A two-term Henyey-Greenstein phase function has been employed to estimate anisotropy coefficient for forward (gfs) and backward scattering (gbs). Experimental trails were performed to assess the repeatability of measurement system: percentage value of standard deviation is generally lower than 8% for angles higher (lower) than 13° (13°). Measurements were performed for the first time on healthy swine pancreas, aiming to investigate the influence of coagulation temperature: gfs decreases from 0.94 (at 25 °C) to 0.93 (at 80 °C). Afterwards, the same set up has been employed for the estimation of g of human pancreas affected by neuroendocrine tumor, which presented an estimated values for gfs of 0.89.

Magnetic resonance-based thermometry during laser ablation on ex-vivo swine pancreas and liver

Laser Ablation (LA) is a minimally-invasive procedure for tumor treatment. LA outcomes depend on the heat distribution inside tissues and require accurate temperature measurement during the procedure. Magnetic resonance imaging (MRI) allows a non-invasive and three-dimensional thermometry of the organ undergoing LA.In this study, the temperature distribution within two swine pancreases and three swine livers undergoing LA (Nd:YAG, power: 2 W, treatment time: 4 min) was monitored by a 1.5-T MR scanner, utilizing two T1-weighted sequences (IRTF and SRTF). The signal intensity in four regions of interest, placed at different distances from the laser applicator, was related to temperature variations monitored in the same regions by twelve fiber Bragg grating sensors. The relationship between the signal intensity and temperature increase was calculated to obtain the calibration curve and to evaluate accuracy, sensibility and precision of each sequence. This is the first study of MR-based thermometry during LA on pancreas. More specifically, the IRTF sequence provides the highest temperature sensitivity in both liver (1.8 ± 0.2 °C−1) and pancreas (1.8 ± 0.5 °C−1) and the lowest precision and accuracy. SRTF sequence on pancreas presents the highest accuracy and precision (MODSFRT = −0.1 °C and LOASFRT = [−2.3; 2.1] °C).

Estimation of anisotropy coefficient of swine pancreas, liver and muscle at 1064nm based on goniometric technique.

Optical properties of tissues are required for theoretical modeling of Laser Ablation in tumor therapy. The light scattering characteristic of tissues is described by the anisotropy coefficient, g. The relationship between the angular distribution of scattered light and g is given by the Henyey-Greenstein (HG) phase function. This work describes the estimation of anisotropy coefficients of ex vivo swine pancreas, liver and muscle at 1064 nm. The intensities of scattered light at fixed angles were measured under repeatability conditions. Experimental data were fitted with a two-term HG, estimating the anisotropy coefficients for the forward (e.g., 0.956 for pancreas, 0.964 for liver and 0.968 for muscle) and the backward (e.g., -0.481 for pancreas, -0.414 for liver and -0.372 for muscle) scattering. Experimental set up employed to estimate the anisotropy coefficient of biological tissues. The image on the left depicts the holder used to house tissue, laser fiber and photodetector; on the left an example of scattered light beam is shown, as well as the effect due to Snell's law.

Endovascular Method for Transplantation of Insulin-Producing Cells to the Pancreas Parenchyma in Swine

Insulin-producing cells are transplanted by portal vein injection as an alternative to pancreas transplantation in both clinical and preclinical trials. Two of the main limitations of portal vein transplantation are the prompt activation of the innate immunity and concomitant loss of islets and a small but significant risk of portal vein thrombosis. Furthermore, to mimic physiological release, the insulin-producing cells should instead be located in the pancreas. The trans-vessel wall approach is an endovascular method for penetrating the vessel wall from the inside. In essence, a working channel is established to the parenchyma of organs that are difficult to access by percutaneous technique. In this experiment, we accessed the extra-vascular pancreatic parenchyma in swine by microendovascular technique and injected methylene blue, contrast fluids and insulin-producing cells without acute adverse events. Further, we evaluated the procedure itself by a 1-year angiographical follow-up, without adverse events. This study shows that the novel approach utilizing endovascular minimal invasiveness coupled to accurate trans-vessel wall placement of an injection in the pancreatic parenchyma with insulin-producing cells is possible. In clinical practice, the potential benefits compared to portal vein cell transplantation should significantly improve endocrine function of the graft and potentially reduce adverse events.This study presents one-year follow-up safety data on the microendovascular trans-vessel wall technique and shows that the technique can be used to transplant insulin-producing cells to the swine pancreas parenchyma.

High-resolution magic angle spinning1H magnetic resonance spectroscopy detects choline as a biomarker in a swine obstructive chronic pancreatitis model at an early stage

Chronic pancreatitis (CP) is a progressive inflammatory and fibrotic disease of the pancreas which encompasses a variety of clinical syndromes ranging from mild to life-threatening complications. Metabolomics has increasingly been applied to identify biomarkers for disease diagnosis with particular interest in diseases at an early stage. In this study, we tested a swine obstructive CP model by subtotal ligation of the main pancreatic duct, and the metabolic profiles of the Bama miniature swine pancreas were investigated using high-resolution magic angle spinning proton magnetic resonance spectroscopy (HR MAS (1)H MRS) combined with principal components analysis (PCA). Increases in lactate and choline for mild CP and decreases in glycerophosphocholine, phosphocholine, betaine and glycine were observed from normal pancreas to mild, moderate and severe CP. PCA results showed visual separations among the groups. The increase of choline at an early stage of CP and the decrease of glycerophosphocholine, phosphocholine, betaine and glycine reveal the pathogenesis of CP at a molecular level. The MRS results presented here demonstrate the potential of metabolic profiles in discriminating a normal pancreas from different stages of CP, which may be used to achieve CP early diagnosis and timely intervention to prevent irreversible destruction of the pancreas.

Experimental assessment of CT-based thermometry during laser ablation of porcine pancreas

Laser interstitial thermotherapy (LITT) is employed to destroy tumors in organs, and its outcome strongly depends on the temperature distribution inside the treated tissue. The recent introduction of computed tomography (CT) scan thermometry, based on the CT number dependence of the tissue with temperature, overcomes the invasiveness of other techniques used to monitor temperature during LITT. The averaged CT number (ROI = 0.02 cm2) of an ex vivo swine pancreas is monitored during LITT (Nd:YAG laser power of 3 W, treatment time: 120 s) at different distances from the applicator (from 4 to 30 mm). The averaged CT number shows a clear decrease during treatment: it is highest at 4 mm from the applicator (mean variation in the whole treatment of −0.256 HU s−1) and negligible at 30 mm, since the highest temperature increase is present close to the applicator (i.e., 45 °C at 4 mm and 25 °C at 6 mm). To obtain the relationship between CT numbers and pancreas temperature, the reference temperature was measured by 12 fiber Bragg grating sensors. The CT number decreases as a function of temperature, showing a nonlinear trend with a mean thermal sensitivity of −0.50 HU °C−1. Results here reported are the first assessment of pancreatic CT number dependence on temperature, at the best of our knowledge. Findings can be useful to further investigate CT scan thermometry during LITT on the pancreas.

Temperature monitoring and lesion volume estimation during double-applicator laser-induced thermotherapy in ex vivo swine pancreas: a preliminary study

Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2mm from both applicators tips, the maximum temperature increase is approximately 60°C downward from the tips, while it increases of about 40°C and 30°C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91 ± 0.09 vs. 0.95cm(3)). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.

Abstract No. 265 - Prediction model, pathology and imaging correlation of acute and chronic outcomes following irreversible electroporation of the pancreas

Purpose To evaluate the acute outcomes and chronic evolution following irreversible electroporation (IRE) tissue ablation in healthy swine pancreas and to correlate ablation size predicted by a numerical model with computed tomography (CT) imaging and pathology. Materials and Methods IRE ablation of porcine pancreatic tissue (body and tail) was performed in 6 Yorkshire pigs under CT guidance. Treatment parameter-ablation size response was evaluated by varying the pulse length (seventy or ninety DC pulses of 70-100 μs length) and the strength of the applied electric field (2-2.5 kV/cm). Two animals each were sacrificed after one day (acute, n=2), 14 days (subacute, n=2) and 28 days (chronic, n=2). Multiphase contrast enhanced computed tomography (CECT) imaging was performed 15 minutes and 24 hours after treatment in all animals, after 14 days in the subacute and after 14 and 28 days in the chronic study group. Biochemical markers were recorded before and 24 hours after the intervention in all animals and 14 days post-procedure in the subacute and chronic study group. Results All IRE ablations were successfully completed and all animals survived without major complications until the planned endpoints of the study at day 1, 14 and 28. Histopathologic results showed necrosis and edema in the acute setting on day 1, partial tissue regeneration after 14 days with signs of fibrosis and glandular atrophy after 28 days. Laboratory enzymes indicated mild to moderate acute amylasemia and lipasemia in all animals after 24 hours but no abnormalities after 14 days. The measured size of the ablation using CT imaging on day 0 and 1 could be correlated with the ablation size predicted through numerical modeling. Conclusion IRE is a feasible method for ablation of pancreatic tissue. CT measured ablation size correlates to the predictions based on numerical simulations.

Feasibility of EUS-guided injection of irinotecan-loaded microspheres into the swine pancreas

LC beads (Biocompatibles International plc) are designed for the time-released delivery of the chemotherapeutic agent irinotecan into focal, hypervascularized, hepatic tumors. To determine the feasibility of EUS-guided injection of LC beads (with/without irinotecan) into the swine pancreas. Survival animal study. Academic center. This study involved 12 Yorkshire swine. LC beads without irinotecan and loaded with up to 300 mg of irinotecan were injected under EUS guidance with a 19-gauge needle into the tail of the pancreas. CT scanning and necropsy with histology were performed at day 7. Feasibility of the injections, gross and microscopic evidence of pancreatic inflammation, and clinical tolerance by the animals. After injection of LC beads with/without irinotecan, in 10 of 12 animals an intrapancreatic, hyperechoic focus with an average diameter of 2.2 cm was visible by EUS, and a hypodense area in the tail of the pancreas was visible by contrast CT. In 2 animals (1 with irinotecan and 1 without) no beads were seen on CT. In 10 of 12 animals, a depot of beads was located in the tail of the pancreas on gross inspection and histology. Drug depot with only localized pancreatic tissue reactions was seen on histopathologic review. Animal study. The EUS-guided injection of LC beads (with/without irinotecan) into the pancreas of the pig is feasible and safe. This technique is a potential minimally invasive local treatment option for locally advanced pancreatic cancer.

Valor nutricional de alimentos para suínos determinado na Universidade Federal de Lavras

Foram conduzidos seis ensaios de metabolismo no Departamento de Zootecnia da Universidade Federal de Lavras (UFLA) no ano de 2002, com objetivo de avaliar a composição química e nutricional de 8 alimentos protéicos e 10 energéticos. Para o primeiro ensaio, foram selecionados animais de peso-vivo médio de 40,4 kg, sendo analisado o farelo de algodão, soja micronizada, farelo de soja, farelo de linhaça, farinha de pâncreas suíno, farinha de vísceras suína, milho comum, milheto em grão e moído, resíduo de bolacha, óleo de canola, óleo de linhaça, óleo de soja, gordura de coco e gordura suína. Para o segundo ensaio, foram selecionados animais de 50,2 kg e foi analisado o farelo de amendoim e milho QPM. Um total de 72 suínos machos, castrados e mestiços (Landrace x Large White), foram utilizados nos ensaios, e a metodologia adotada foi a da coleta total de fezes e urina. Desta forma, cada alimento foi testado em três repetições. Os valores obtidos de coeficiente de digestibilidade da proteína bruta (CDPB), valores de energia digestível (ED) e energia metabolizável (EM) para os alimentos protéicos de origem vegetal foram 66,2%, 2480 kcal/kg, 2190 kcal/kg, para farelo de algodão; 77,73%, 2365 kcal/kg, 2289 kcal/kg, para o farelo de girassol; 72,3%, 2880 kcal/kg, 2580 kcal/kg para farelo de linhaça; 86,5%, 3430 kcal, 3360 kcal/kg para farelo de soja 46% proteína bruta; 86,8%, 4580 kcal/kg, 4350 kcal/kg para soja micronizada; 81,2%, 3292 kcal/kg, 3146 kcal/kg para o farelo de amendoim. Para os alimentos protéicos de origem animal foram 47,3%, 3470 kcal/kg, 3310 kcal/kg para farinha de pâncreas suína; 81,3%, 3660 kcal/kg, 3535 kcal/kg para farinha de vísceras suína. Para os alimentos energéticos de origem vegetal foram 84,4%, 3220 kcal/kg, 3185 kcal/kg para a farinha de bolacha; 85,3%, 3480 kcal, 3320 kcal/kg para o milho moído; 81,2%, 3308 kcal/kg; 3257 kcal/kg para o milho QPM; 86,2%, 3213 kcal/kg, 3048 kcal/kg para o milheto moído; 83,5%, 3123 kcal/kg, 2950 kcal /kg para o milheto em grão inteiro. Para óleos e gorduras os valores de energia digestível (ED) e energia metabolizável (EM) foram 8630 kcal/kg, 8340 kcal/kg para o óleo de canola; 8380 kcal/kg, 8220 kcal/kg para o óleo de linhaça; 8670 kcal/kg, 8340 kcal/kg para o óleo de soja; 8110 kcal/kg, 7960 kcal/kg para a gordura de coco; 8630 kcal/kg, 8280 kcal/kg para a gordura suína. De uma maneira geral, os dados analisados mostram variações na composição química, digestibilidade e valores energéticos dos alimentos, em relação aos citados nas tabelas brasileiras e estrangeiras, e valores citados por outras pesquisas referenciadas nas literaturas consultadas. Os valores obtidos no presente trabalho, além de fornecerem subsídios para aumentar as informações do banco de dados como forma de contribuir na elaboração de uma tabela nacional de alimentos para suínos, também poderão possibilitar melhorias técnicas para a formulação de rações para suínos.

Swine pancreas preservation with celsior solution

Swine pancreas preservation with celsior solution

PEHPS medium: an alternative for axenic cultivation of Entamoeba histolytica and E. invadens

Knowledge of Entamoeba histolytica biology in the last 17 years has been acquired largely as a consequence of this parasite's axenic cultivation in TPS-1 or TYI-S-33 media. Unfortunately, there are often low yields in these media, due to variability of their main components, Panmede and yeast extract. We describe a medium, PEHPS, of which the main components are extracts of ox liver, and ox and swine pancreas (EHP). 5 strains of E. histolytica and 2 of E. invadens were quickly and easily adapted to PEHPS and serially cultivated for 3 years. Yields progressively rose initially, and then became stable. Depending on the strain, average yields in the last 6 months of this study were 1·3 to 3·1 × 10 5 amoebae/ml for E. histolytica and 5·5 to 5·7 × 10 5 for E. invadens. All the 18 EHP batches tested supported vigorous amoebal growth. PEHPS had 2 additional advantages: (a) it was stable at 4 °C or 25 °C for 9 months, and at −10 °C for at least 2 years, and (b) it supported amoebal growth with inocula as low as one trophozoite/ml. PEHPS avoids the variability shown by TPS-1 and TYI-S-33, and could therefore be a good alternative for axenic amoebal cultivation.