Kidney Of Piglets Research Articles

Adaptation of african swine fever virus (Asfarviridae: Asfivirus)to growth in the continuous culture PPK-66b cells by the method of accelerated passaging

African swine fever virus (ASF) is a large, enveloped virus with an icosahedral capsid morphology and a double-stranded DNA genome ranging in size from 170 to 190 kb. The replication cycle proceeds in two phases, the early phase lasting 4-6 hours and the late 8-20 hours after infection. The adaptation of the ASF virus to growth in continuous cell lines makes efficient and reliable genetic analysis and more accurate interpretation of its results. Adaptation of a new isolate of the ASF virus to growth in a continuous cell line by the method of accelerated passages and preliminary genetic analysis of the resulting strain. For virus isolation and passaging of the ASF virus, a porcine leukocyte cell culture (PL) and continuous cell cultures of porcine origin (ST, PK, PPK-66b) were used with Eagle MEM and HLA essential media with 10% porcine or fetal serum. The article presents data on the isolation and analysis of the changes in the reproductive properties of a new African swine fever (ASF) virus isolate in the process of adaptation to growth in a continuous piglet kidney cell culture clone b (PPK-66b). The current state of the problem of cultivation of the ASF virus, the features of its reproduction, and the basis of the genetic differentiation of its isolates are described in detail. Understanding the uniqueness of the nature of the ASF virus determined the approaches to the processes of its cultivation and adaptation. In this regard, the results of studies of cultural properties, and analysis of the nucleotide sequence of 6 genes of the new isolate, as well as phylogenetic analysis of these genes with already known strains and isolates of the ASF virus are presented. A new strain obtained in the process of cell adaptation of ASVF/Znaury/PPK-23 ASF virus by the accelerated passaging method reaches a high level of reproduction in 72 hours with an accumulation titer of 7.07 lg HAdE50/cm3. Primary genetic analysis allowed to establish the main phylogenetic relationships of the newly isolated strain with previously known variants of the current ASF panzootic.

Surgical simulation of pediatric laparoscopic dismembered pyeloplasty: Reproducible high-fidelity animal-tissue model

To provide a high-fidelity, animal tissue-based model for the advanced surgical simulation of laparoscopic dismembered pyeloplasty in infants and children. A previously described animal tissue model using chicken crop was surgically modified and attached to piglet kidney specimens in order to provide organ model realistically resembling infant and children hydronephrosis for simulation of dismembered laparoscopic pyeloplasty. Dismembered pyeloplasty could then be carried out in a standard pelvi-trainer using a standard instrumentation as in a regular case. The model created could prove to be a high-fidelity, animal tissue model for the surgical simulation of dismembered pyeloplasty. The surgical modification of the used animal tissues of chicken crop and piglet kidney respectively used in this fusion model was able to provide a high grade of resembling a realistic organ situs for infant and pediatric pyeloplasty, respectively. The surgical procedure could be carried out as a simulation of a regular case while providing high-grade realistic anatomy, adequate sizes of a dilated renal pelvis and of the ureter, respectively. Biological as well as haptic conditions of the tissue were able to resemble human tissue in a high grade as well. Despite a live animal model has been described for dismembered pyeloplasty, its time-consuming creation and possible conflict concerning animal welfare cadaver models are more practicable for daily simulation. In literature so far animal-tissue models described range from folded chicken skin to a chicken crop model. While these types of models have its own advantages and disadvantages none of them provide adequate anatomical relations. By dissecting chicken crop and fixating it to a piglet's kidney this limitation could be overcome and furthermore will enable future modifications for a perfused model for laparoscopic dismembered pyeloplasty. The fusion of a previously described tissue model of chicken crop for simulation of pyeloplasty along with also previously used piglet kidneys for surgical simulation can provide a highly realistic model for surgical simulation of pediatric dismembered laparoscopic pyeloplasty. In addition, this model rules out the disadvantage of native animal kidney specimens which the lack of pathology of a dilated renal pelvis. Surgical modification is an established method to provide high-fidelity animal tissue models for surgical simulation and therefore training of complex procedures, respectively. For simulation purposes in pediatric laparoscopic urology, i.e., reconstructive procedures such as dismembered pyeloplasty this model appears to be promising in terms of providing realistic pathology in pediatric dimensions.

Response of antioxidant status in kidney of pigs exposed to aflatoxin B1 to dietary grape seed meal

Abstract This study investigated the effects of dietary inclusion of grape seed meal (GSM) on antioxidant markers in kidney of aflatoxin B1 fed pigs. Twenty-four cross-bred pigs (TOPIG-40) were randomly assigned to one of the four experimental diets: control (Control), aflatoxin B1 (diet contaminated with 320 μg AFB1/kg feed), grape seed meal (diet with 8% GSM) and AFB1+GSM (320 μg AFB1/kg feed + 8% GSM) for 30 days. Aflatoxin B1 induced oxidative damage and showed lower antioxidant status in kidney after 30 days. CAT and SOD activity measured in kidneys revealed significant differences when comparing the GSM+AFB1 group with the AFB1 group. Additionally, GSM diet alone did not affect CAT and SOD levels in kidneys of piglets compared with the control group, suggesting that they are maintained at physiological levels. We did not detect any effects of GSM on GPx and TAS. Including GSM into piglets’ diet significantly lowered lipid peroxidation induced by AFB1, while it did not affect it compared with the control group. The present study demonstrated the ability of GSM to alleviate the effects induced by the toxin evidenced by the improvement in the antioxidant status, and suggests the potential applicability of GSM as mycotoxin adsorbent in animal feed.

Development and Validation of a Multi-detection Confirmatory Method for Antibiotics Determination in Piglet Kidneys by UHPLC-TOF-MS According Commission Decision 2002/657/EC

The combination of ultra-high-performance liquid chromatography (UHPLC) with time-of-flight mass spectrometry (ToF-MS) is one of the most powerful analytical tools in terms of selectivity, sensitivity and speed. However, due to the gap on regulation and guidelines concerning the validation criteria for the use of ToF-MS methodology not only for screening but also for confirmatory and quantification purposes, this study presents, for the first time, an approach on how to use the referred methodology for confirmatory and quantification purposes. Thus, an UHPLC-ToF-MS method was developed and validated for the simultaneous determination of 43 antibiotic residues from 7 different families (tetracyclines, sulfonamides, quinolones, penicillins, macrolides, cephalosporins and trimethoprim) in piglet kidneys as a confirmatory method. A simple sample preparation consisting of extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA) followed by solid-phase extraction (SPE) with a hydrophilic-lipophilic balanced (HLB) cartridge and finalized with a defatting step with n-hexane was used. The methodology was validated according the Commission Decision 2002/657/EC, by defining suitable criteria for antibiotic identification, as well as by evaluating required parameters like selectivity, specificity and ruggedness that fulfil the required criteria. The calculated values of decision limit (CCα) and of detection capacity (CCβ) for antibiotics with established maximum residue limits (MRLs) fully complied with required criteria. For antibiotics for which no MRL was set, values ranging from 0.2 to 0.5 μg kg−1 and from 0.5 to 0.8 μg kg−1 were achieved for CCα and for CCβ, respectively. Linearity (all R2 > 0.95), recovery (81.4–110.0%) (lowest values of 4.6% and 7.1% were obtained for repeatability and for reproducibility, respectively), LODs (0.04–13.0 μg kg−1), LOQs (0.09–32.0 μg kg−1) and matrix effects (35.5–118.1 %) were also evaluated. After validation, the method was applied to analyse piglet kidney samples. Antibiotic residues were determined in 10 of the 15 analysed samples. However, all the antibiotics concentrations were below the MRLs.

Tissue-specific profiling reveals modulation of cellular and mitochondrial oxidative stress in normal- and low-birthweight piglets throughout the peri-weaning period

Weaning is known to induce important nutritional and energetic stress in piglets. Low-birthweight (LBW) piglets, now frequently observed in swine production, are more likely to be affected. The weaning period is also associated with dysfunctional immune responses, uncontrolled inflammation and oxidative stress conditions that are recognized risk factors for infections and diseases. Mounting evidence indicates that mitochondria, the main cellular sources of energy in the form of adenosine 5′ triphosphate (ATP) and primary sites of reactive oxygen species production, are related to immunity, inflammation and bacterial pathogenesis. However, no information is currently available regarding the link between mitochondrial energy production and oxidative stress in weaned piglets. The objective of this study was to characterize markers of cellular and mitochondrial energy metabolism and oxidative status in both normal-birthweight (NBW) and LBW piglets throughout the peri-weaning period. To conduct the study, 30 multiparous sows were inseminated and litters were standardized to 12 piglets. All the piglets were weighted at day 1 and 120 piglets were selected and assigned to 1 of 2 experimental groups: NBW (n = 60, mean weight of 1.73 ± 0.01 kg) and LBW piglets weighing less than 1.2 kg (n = 60, 1.01 ± 0.01 kg). Then, 10 piglets from each group were selected at 14, 21 (weaning), 23, 25, 29 and 35 days of age to collect plasma and organ (liver, intestine and kidney) samples. Analysis revealed that ATP concentrations were lower in liver of piglets after weaning than during lactation (P < 0.05) thus suggesting a significant impact of weaning stress on mitochondrial energy production. Oxidative damage to DNA (8-hydroxy-2′-deoxyguanosine, 8-OHdG) and proteins (carbonyls) measured in plasma increased after weaning and this coincides with a rise in enzymatic antioxidant activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) (P < 0.05). Mitochondrial activities of both GPx and SOD are also significantly higher (P < 0.05) in kidney of piglets after weaning. Additionally, oxidative damage to macromolecules is more important in LBW piglets as measured concentrations of 8-OHdG and protein carbonyls are significantly higher (P < 0.05) in plasma and liver samples, respectively, than for NBW piglets. These results provide novel information about the nature, intensity and duration of weaning stress by revealing that weaning induces mitochondrial dysfunction and cellular oxidative stress conditions which last for at least 2 weeks and more severely impact smaller piglets.

MicroRNA profiling in kidney in pigs fed ochratoxin A contaminated diet

OTA is a toxic metabolite produced by fungus belonging to Aspergillus and Penicillium genera. Kidney is the main target of this toxin; OTA is considered as one of the etiological factors at the origin of the human Balkan endemic nephropathy. microRNA are short non-coding transcrips (18–22 nucleotides in length) regulating key cellular processes. Various miRNAs have been established to play important roles in development of renal carcinoma and urothelial cancer. The objective of this study is to analyse the miRNA profiling in the kidney of piglets experimentally intoxicated with feed contaminated with OTA. Fifteen piglets (five pigs/group) were randomly distributed into 3 groups, fed normal diet (Group 1: control), or diets contaminated with OTA in two concentrations: 50 μg OTA/kg feed (Group 2: 50 μg OTA/kg feed) or 200 μg OTA/kg feed (Group 3: 200 μg OTA/kg feed) for 28 days. At the end of the experiment blood samples were taken for serological analyses. Animals from control group and 200 μg OTA/kg feed were sacrificed and kidney samples were taken for histological and molecular analyses. As resulted from molecular profiling study there are 8 miRNA differentially expressed in OTA kidney vs control kidney, in which five miRNA were overexpressed in the kidney of OTA intoxicated animals: miR-497 (FC = 6.34), miR-133a-3p (FC = 5.75), miR-423-3p (FC = 5.48), miR-34a (FC = 1.68), miR-542-3p (1.65) while three miRNA were downregulated: miR-421-3p (FC = −3.96); miR-490 (FC = −3.87); miR-9840-3p (FC = −2.13). The altered miRNAs as effect of OTA are strongly connected to the engine of cancer, disturbing nodal points in different pathways, as TP53 signalling. This proof-of-concept study proves the actual utility of miRNAs as biomarkers of mycotoxin exposure, including OTA.

Effects of deoxynivalenol- and zearalenone-contaminated feed on the gene expression profiles in the kidneys of piglets.

ObjectiveFusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEN), common contaminants in the feed of farm animals, cause immune function impairment and organ inflammation. Consequently, the main objective of this study was to elucidate DON and ZEN effects on the mRNA expression of pro-inflammatory cytokines and other immune related genes in the kidneys of piglets.MethodsFifteen 6-week-old piglets were randomly assigned to three dietary treatments for 4 weeks: control diet, and diets contaminated with either 8 mg DON/kg feed or 0.8 mg ZEN/kg feed. Kidney samples were collected after treatment, and RNA-seq was used to investigate the effects on immune-related genes and gene networks.ResultsA total of 186 differentially expressed genes (DEGs) were screened (120 upregulated and 66 downregulated). Gene ontology analysis revealed that the immune response, and cellular and metabolic processes were significantly controlled by these DEGs. The inflammatory stimulation might be an effect of the following enriched Kyoto encyclopedia of genes and genomes pathway analysis found related to immune and disease responses: cytokine-cytokine receptor interaction, chemokine signaling pathway, toll-like receptor signaling pathway, systemic lupus erythematosus (SLE), tuberculosis, Epstein-Barr virus infection, and chemical carcinogenesis. The effects of DON and ZEN on genome-wide expression were assessed, and it was found that the DEGs associated with inflammatory cytokines (interleukin 10 receptor, beta, chemokine [C-X-C motif] ligand 9, CXCL10, chemokine [C-C motif] ligand 4), proliferation (insulin like growth factor binding protein 4, IgG heavy chain, receptor-type tyrosine-protein phosphatase C, cytochrome P450 1A1, ATP-binding cassette sub-family 8), and other immune response networks (lysozyme, complement component 4 binding protein alpha, oligoadenylate synthetase 2, signaling lymphocytic activation molecule-9, α-aminoadipic semialdehyde dehydrogenase, Ig lambda chain c region, pyruvate dehydrogenase kinase, isozyme 4, carboxylesterase 1), were suppressed by DON and ZEN.ConclusionIn summary, our results indicate that high concentrations of DON and ZEN suppress the inflammatory response in kidneys, leading to potential effects on immune homeostasis.

Comparative effect of ochratoxin A on inflammation and oxidative stress parameters in gut and kidney of piglets

Ochratoxin A (OTA) is a secondary metabolite produced by fungi of Aspergillus and Penicillium genra. OTA is mainly nephrotoxic but can also cause hepatotoxicity, mutagenicity, teratogenicity, neurotoxicity and immunotoxicity. As recent studies have highlighted the close relationship between gastrointestinal tract and kidney, as principal organs involved in absorption and respective excretion of xenobiotics, the aim of the present study was to analyze the effect of a subchronic exposure (30 days) to 0.05 mg/kg OTA on immune response and oxidative stress parameters at the level of intestine and kidney of young swine. The experiment was realised on twelve crossbred weaned piglets randomly allotted to both control group or toxin group fed 0.050 mg OTA/kg feed. Our results have shown that a subchronic intoxication with a low dose of OTA for 30 days affected the immune response and the anti-oxidant self-defense at gut and kidney level. The gene expression of both markers of signaling pathways involved in inflammation and inflammatory cytokines were affected in a much higher extent in the gut than in the kidney Of OTA intoxicated piglets.

Failure of Neonatal B-Cell Tolerance Induction by ABO-Incompatible Kidney Grafts in Piglets

ABO-incompatible (ABOi) infant heart transplantation results in B-cell tolerance to graft A/B antigens, confirming human susceptibility to acquired immunologic or "neonatal" tolerance as described originally in murine models. Starting with this clinical observation, we sought to model neonatal ABOi organ transplantation to allow mechanistic studies of tolerance. Plasma anti-A/B antibodies were measured over time in piglets to establish developmental antibody kinetics. Blood group O piglets received kidney allografts from group A (AO-incompatible) or group O (AO-compatible) donors under cyclosporine immunosuppression. Anti-A antibodies were measured serially after transplantation; A/H antigen expression and allograft rejection were assessed in graft biopsies. Anti-A antibodies developed in naïve piglets in a kinetic pattern analogous to human infants; anti-B remained low. After transplantation, anti-A antibodies developed similarly in AO-incompatible and AO-compatible groups and were not suppressed by cyclosporine. A/H antigen expression was persistent in all graft biopsies; however, A/H antigens were not detected in vascular endothelium. Cellular and antibody-mediated rejection was absent or minimal in early and late biopsies in both groups, with one exception. Naturally delayed isohemagglutinin production in piglets is analogous to the developmental kinetics in human infants. However, in contrast to deficient anti-A antibody production as seen long-term after "A-into-O" infant heart transplant recipients, normal anti-A antibody production after "A-into-O" piglet kidney transplantation indicates that tolerance did not develop despite graft A antigen persistence. These findings suggest that the impact on the host immune system of exposure to nonself ABH antigens during early life in human heart versus porcine kidney grafts may depend on expression in vascular endothelium.

Effectiveness of maifanite in reducing the detrimental effects of aflatoxin B1 on hematology, aflatoxin B1 residues, and antioxidant enzymes activities of weanling piglets

A feeding trial was conducted to evaluate the effectiveness of maifanite, which is mainly composed of aluminosilicate, in reducing the adverse effects of aflatoxin B1 (AFB1) on hematology, AFB1 residues, and antioxidant enzymes activities in weaning piglets. A total of 32 (9.28±0.17kg BW) individually housed crossbred piglets (Duroc×Landrace×Large white) were randomly allotted to 1 of 4 dietary treatments in a 2×2 factorial arrangement with 8 replicates per treatment. The dietary treatments included 2 AFB1 levels (5.3 and 372.8μg/kg) and 2 maifanite levels (0% and 1%). No differences in average daily gain, average daily feed intake, and gain to feed ratio were observed among treatments. Ingestion of the AFB1-contaminated (AF) diets (372.8μg/kg of AFB1) reduced (P<0.05) the numbers of neutrophil, monocyte, and total leukocyte. There were no effects of AFB1 on gamma glutamyltransferase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase activities, and total protein, albumin, urea N, total bilirubin, IgG, IgA, and IgM concentrations in serum. Aflatoxin B1 was found in the liver and kidney of piglets fed the AF diets. Piglets fed the AF diets reduced (P<0.05) the total superoxide dismutase, glutathione peroxidase, and catalase activities in serum. However, total superoxide dismutase activity in the liver was increased (P<0.05) in piglets fed the AF diets compared with those fed the basal diets (5.3μg/kg of AFB1). There was an interaction (P=0.003) in erythrocyte, but piglets fed the diets containing maifanite had greater erythrocyte and lymphocyte (P=0.035) numbers than those fed the diets without maifanite. The AFB1 levels in the liver and kidney of piglets fed the AF diet containing maifanite were 29.6% and 41.2% lower, respectively, than those of piglets fed the AF diet alone. Although there was an interaction (P=0.011), piglets fed the diets containing AFB1 and maifanite had greater serum T-SOD activity compared with those fed the diets with no maifanite. In conclusion, the addition of maifanite to the AF diet resulted in partial restoration of hematology and antioxidant enzymes activities and reduced AFB1 levels in the liver and kidney.

Investigating piglet kidney vitamin A concentrations after high dose supplementation at birth

Potential metabolism and toxicity issues with infant vitamin A dosing procedures have led to a vested interest by the World Health Organization. Whole body retinoid trafficking was under investigation by determination of serum, liver, lung, kidney, adrenal, and spleen retinoid concentrations of piglets born from vitamin A depleted sows and dosed at birth with 25K, 50K, or 200K IU preformed vitamin A. These doses represent levels currently administered to newborn children and mothers in regions with high prevalence of vitamin A deficiency. Retinoids are known to be stored in these tissues with kidney being the primary extrahepatic storage site. In this study, kidneys were analyzed by grinding with sodium sulfate and adding C‐23 alcohol as an internal standard. Dichloromethane was used to extract retinol and retinyl esters. All samples were saponified, extracted, and injected onto an HPLC system to analyze total retinol content. A subgroup was also analyzed unsaponified to elucidate the retinyl ester profile. Data will be used collectively with other organ and serum data to have a complete model for vitamin A circulation and storage under a deficient status followed by high dose paradigm.Grant Funding Source: World Health Organization

Cardiopulmonary Bypass and Its Direct Effects on Neonatal Piglet Kidney Morphology

Renal failure after open heart surgery is a serious complication even in the pediatric population. The aim of the present study was to analyze morphological changes after cardiopulmonary bypass (CPB) surgery in a neonatal piglet model. The kidneys of newborn piglets sacrificed 6 h after CPB were examined (CPB; n = 4) regarding tubular dilatation, vacuole formation, leukocytic infiltration, epithelial destruction, and interstitial edema. Thereafter, the findings were compared with the morphology of normal (untreated) neonatal piglet kidneys (control; n = 4). All changes but the interstitial edema were statistically significant if compared with the normal renal tissue: tubular dilatation (CPB vs. control P < 0.05), vacuole formation (CPB vs. control P < .05), leukocytic infiltration (CPB vs. control P < 0.05), and epithelial destruction (CPB vs. control P < 0.001). In conclusion, CPB induces significant changes in the morphology of the neonatal piglet kidneys.

Effectiveness of mycotoxin sequestration activity of micronized wheat fibres on distribution of ochratoxin A in plasma, liver and kidney of piglets fed a naturally contaminated diet

A study was carried out to determine the ability of dietary micronized wheat fibres (MWF) to decrease the levels of ochratoxin A (OTA) in plasma, kidney and liver of piglets fed a naturally contaminated diet. A total of 96 piglets (weighting 11.4 ± 1.5 kg) were fed one of four different diets for 28 days. Diets included (1) control diet, (2) control diet with MWF (1%), (3) OTA naturally contaminated diet (117.45 ± 4.74 ng/g), (4) OTA naturally contaminated diet (118.13 ± 2.85 ng/g) with MWF (1%). No difference in feed efficiency ( P > 0.05) could be observed between the different diets. The absolute weight of kidneys and liver were significantly higher in pigs fed the OTA-contaminated diet (diet 3) as compared to the control diet (diet 1) or to the control diet amended with MWF (diet 2) ( P < 0.05). However the use of MWF (diet 4) significantly protected against these weight changes. A significant protective effect of MWF was also observed in terms of OTA concentration in plasma (45.6% decrease), kidney (40.8% decrease) and liver (26.5% decrease). These results suggest that the addition of MWF is effective in decreasing the bioavailability of OTA from contaminated diets in piglets.

Effects of ochratoxin a on some production traits, lipid peroxide and glutathione redox status of weaned piglets

The effect of feeding ochratoxin A (OTA) contaminated diet (379.6 and 338.1 microg/kg in starter and grower diets) on production traits, lipid peroxidation and some parameters of the glutathione redox system were investigated in weaned piglets over a seven-week period. Feed intake and feed conversion ratio (FCR) did not differ significantly, but in the first phase (0-28 days) the daily weight gain was significantly lower in the piglets fed the OTA-contaminated diet. Lipid peroxidation, as measured by the amount of malondialdehyde, glutathione content and glutathione peroxidase activity, did not change significantly in the blood plasma and red blood cell haemolysate in the OTA-loaded group, while malondialdehyde content increased significantly in the liver and markedly but not significantly in the kidney of piglets fed OTA-contaminated feed. Glutathione content did not differ significantly in the studied organs of the two groups while glutathione peroxidase activity of the OTA-loaded animals was significantly lower both in the liver and in the kidney. The results suggest that the use of feed-stuffs contaminated with low levels of OTA for seven weeks did not cause marked differences in the production traits or in lipid peroxidation and amount or activity of the glutathione redox system in the blood plasma, red blood cells and kidney, while significant changes occurred in the liver homogenate.

Sensitivity of primary cells immortalised by oncogene transfection for the detection and isolation of foot-and-mouth disease and swine vesicular disease viruses

Primary cells derived from calf thyroid (CTY), calf kidney (CK) and piglet kidney (PK) were immortalised by oncogene transfection and their susceptibility to infection by foot-and-mouth disease (FMD) virus and swine vesicular disease (SVD) virus examined. Eighty-five immortalised cell lines (47 CTY, 20 CK and 18 PK) proved stable upon repeated cell culture passage and many supported the growth of FMD virus and several of the PK cell lines supported SVD virus. However, none of the immortalised lines exhibited either the degree of sensitivity or the specificity for all virus serotypes and strains as shown by primary CTY and IB-RS-2 cell cultures which are routinely employed for vesicular virus diagnosis.

Involvement of apoptosis in the endotoxemic lesions of the liver and kidneys of piglets.

The involvement of apoptosis was evaluated in lesions of endotoxemic piglets. A single injection with E. coli O111:B4 lipopolysaccharide (LPS) induced foci of coagulative necrosis in the liver and kidneys. No significant change was observed in these organs at 1.5 hr after LPS injection, but at 6 hr, epithelial cells with chromatin condensation or fragmentation and apoptotic bodies were visible. Foci of coagulative necrosis were formed within 24 hr after LPS inoculation. In and adjacent to the necrotic foci, dead hepatocytes with nuclear condensation or fragmentation were scattered. These dead cells were positively stained by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) methods. Electronmicroscopy revealed apoptotic cells with condensed or fragmented homogeneous nuclear chromatin, and necrotic cells with irregularly destroyed nuclei and cytoplasmic membranes. Apoptotic cell death were also observed in parietal cells of the stomach and lymphocytes in the lymphatic system. DNA ladders with approximately 200-bp multimers were observed in hepatic, renal and thymic samples prepared after 6 and 24 hr of LPS injection by agarose gel electrophoresis. These results suggest that apoptosis is involved in the pathology of swine endotoxemia.

Papillary morphology in adult human kidneys and in baby and adult pig kidneys.

The morphology of the renal papillae was studied by inspection in a series of: (1) Hampshire/Duroc piglet kidneys; (2) Danish Landrace adult pig kidneys, and (3) kidneys obtained at necropsy from adult patients. In both man and pig two main types of papillae were found: (1) a single or 'simple' papilla which drains one renal lobe, and (2) a fused or 'compound' papilla which drains two or more renal lobes. Compound papillae were found most frequently in the Hampshire/Duroc kidneys and least frequently in the human kidneys. In all three groups compound papillae were found most frequently in the upper pole. Intrarenal backflow during retrograde pyelography in the piglet kidney at intrapelvic pressures of 30-35 mm Hg (moderate) and of 70-75 mm Hg (high) was related to the morphology of the individual papilla. Both types of papilla could be divided into an open type containing at least two round or oval orifices of the papillary ducts and a closed type with small, often slit-like orifices. At moderate intrapelvic pressure intrarenal backflow occurred mainly in the open compound papillae whereas at high intrapelvic pressure it occurred in nearly all open compound papillae and in about 50% of the open simple papillae. It is concluded that papillary morphology plays an important role in the predominant upper polar occurrence of intrarenal backflow/intrarenal reflux during micturition cystography and in the higher frequency of intrarenal backflow in the mid-zone than in the lower pole in adult human beings.

EFFECT OF DIETARY SELENIUM ON GLUTATHIONE PEROXIDASE ACTIVITY IN PIGLETS

Two experiments were conducted to measure the effect of dietary selenium on glutathione (GSH) peroxidase activity in plasma and body organs of growing pigs. In experiment 1, 12 piglets weaned at 2 wk and 18 weaned at 4 wk were fed for a period of 5 wk either a selenium-deficient basal diet or the same diet supplemented with 0.1 ppm selenium as sodium selenite. Three levels of dietary vitamin E supplemented as dl-alpha-tocopheryl acetate were also included in this experiment in a factorial arrangement with selenium. Vitamin E was shown to have no effect on GSH-peroxidase activity. In contrast, dietary selenium exerted a significant effect on the activity of the seleno-enzyme in the plasma, pancreas, heart, lungs and kidneys of piglets. The kidneys showed the highest GSH-peroxidase activity of the organs studied. Supplemental selenium resulted in a marked increase in plasma GSH-peroxidase activity of the piglets weaned at 2 wk, and maintained a high level of activity for those weaned at 4 wk. Pancreatic activity of this enzyme in selenium-deficient animals showed a drop to about one-third the activity observed in selenium-supplemented piglets after a 5-wk period. GSH-peroxidase in heart muscle showed the same response that was observed in the pancreas. The reduction in activity of this enzyme in lungs and kidneys was much greater than in pancreas and heart. No measurable amounts of GSH-peroxidase were observed in the liver of piglets either with or without selenium supplementation. In experiment 2, six pairs of male-female piglets weaned at 2 wk of age were fed either a selenium-deficient or a selenium supplemented diet. During the 20-wk period, selenium-supplemented piglets showed an average GSH-peroxidase activity in plasma 8.2-fold higher than selenium-deficient animals. After 2 wk, selenium-deficient piglets showed an extremely low activity of the seleno-enzyme in the plasma. Thus, the measurement of GSH-peroxidase in plasma of the live animal appears to be a reliable index of nutritional selenium status in piglets.

Development of renal tubular transports of TEA and PAH in the puppy and piglet.

Simultaneous accumulations in renal cortical slices of tetraethylammonium and p-aminohippurate were studied. Slices were obtained from fetal puppies and newborns. Newborns were sacrificed at intervals from birth to 9 weeks. Slice-to-medium ratios (S/M) were compared for adult, pregnant, and postpartum dog renal slices. Newborn piglets' kidneys were studied similarly. It was found that these two transport systems developed independently in the fetal and newborn puppy. The transport of TEA was low at birth and progressively rose to the adult value at 9 weeks. The PAH transport system was active in fetal and newborn tissues. Transports of both TEA and PAH were absent under anaerobic conditions. Acetate stimulated TEA and PAH slice uptakes to the same extent as in the adult. In the piglet the surface slice of the kidney showed low transports of TEA and PAH for the first 2 weeks. At 4 weeks both transport systems increased to equal those in the slices of the lower cortex. The lower cortical slices accumulated TEA and PAH from birth to 8 weeks of age at a fixed rate. The TEA S/M in the piglet at birth was more than twice that in the dog. PAH was accumulated in a predominantly conjugated but unidentified form in the piglet kidney slice.