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Genetic predisposition to coronavirus disease 2019 (COVID-19) may contribute to its morbidity and mortality. Because cytokines play an important role in multiple phases of infection, we examined whether commonly occurring, functional polymorphisms in macrophage migration inhibitory factor (MIF) are associated with COVID-19 infection or disease severity., This work was supported by National Institute of Health (NIH) [1R01-AR078334 (RB), 5R01-AI51306 (RB), R01-HL155948 (MS, RB), 1R01AG056728 (IK), T32AR07107 (JPY) and KL2 TR001862 (JJS)]; the European Commission (DB) – NextGenerationEU (Regulation EU 2020/2094) through CSIC's Global Health Platform (PTI Salud Global), and Junta de Castilla y León (Programa Estratégico Instituto de Biología y Genética Molecular (IBGM), Junta de Castilla y León (CCVC8485); and the National Natural Science Foundation of China [#81901669 (WF)].

Chronic obstructive pulmonary disease (COPD) represents a chronic inflammatory disorder of the airways induced mainly by cigarette smoking. In the current study, cigarette smoke extract (CSE) was used to develop an in vitro COPD model using human bronchial epithelium (HBE) cells to expound the possible role of microRNA-29b (miR-29b) in COPD. Firstly, miR-29b and interleukin (IL)-22 expression was assessed in serum of 20 healthy non-smokers, 20 healthy smokers and 20 COPD patients as well as CSE-treated HBE cells. Then, miR-29b and IL-22 expression was altered to evaluate their functions in Th17/Treg ratio. miR-29b inhibited Th17/Treg ratio and levels of IL-22; whereas overexpression of IL-22 reversed these trends. Moreover, rescue experiments found that IL-22 neutralized the repressive effects of miR-29b on Th17/Treg ratio and inflammatory response. Finally, we found that miR-29b blocked the JAK/STAT3 pathway in CSE-treated HBE cells. These data highlighted that miR-29bs modulated Th17/Treg imbalance in CSE-induced experimental COPD through inhibition of IL-22-dependent JAK/STAT3 pathway.

Highlights: • NW Pacific ice-rafted debris found further south than previously thought. • Largest iceberg events were comparable in magnitude to N Atlantic Heinrich Events. • Iceberg flux to ODP Site 1207 was episodic throughout the late Quaternary. • Kamchatka-Koryak bergs frequently reached south of the N Pacific Subarctic Front. • Ice-rafting and climate contrast sharply between the last two glacial periods. Abstract: The ice-rafted-debris (IRD) record of the open Northwest Pacific points towards the existence of substantial glacial ice on the Northeast Siberian coast during the late Quaternary. However, the scale and timing of glaciation and de-glaciation remains controversial due to the dearth of both onshore and offshore records. Existing IRD data suggests at least one event of dynamic and abrupt change during mid-late Marine Isotope Stage (MIS 3) which mimics the massive collapse of the Laurentide ice sheet during Heinrich Events. It is uncertain whether other events of this magnitude occurred during the late Quaternary. Here we present a ∼160,000 yr IRD series, planktic foraminiferal counts and an age model, derived from a benthic O curve, radiocarbon dates and tephrochronology, from core ODP 1207A (37.79°N, 162.75°E), revealing the presence of low but episodic flux of IRD. We conclude that glacial Northwest Pacific icebergs spread further south than previously thought, with icebergs emanating from Northeast Siberia being transported to the transition region between the subpolar and subtropical waters, south of the subarctic front during at least the Quaternary's last two glacial periods. The episodic nature of the 1207A IRD record during the last glacial, combined with coupled climate-iceberg modelling, suggests occasional times of much enhanced ice flux from the Kamchatka-Koryak coast, with other potential sources on the Sea of Okhotsk coast. These findings support the hypothesis of a variable but extensive ice mass during the last glacial over Northeast Siberia, particularly early in the last glacial period, behaving independently of North American and Eurasian ice masses. In strong contrast, IRD was absent during much of the penultimate glacial Marine Isotope Stage (MIS) 6 suggesting the possibility of very different Northeast Siberian ice coverage between the last two glacial periods.

In order to optimize the fatigue strength of 7075 Al alloy, the hardness, tensile and fatigue tests as well as the microstructure observation under different aging conditions were investigated. The result indicates that, with the aging time increasing, the precipitation spacing first decreases and then increases, which leads to the hardness and tensile strength first increasing and then decreasing. With the increase of yield strength, the fatigue strength increases first and then decreases, resulting in an optimization of fatigue strength. Especially, the specimen aged at 120 °C for 48 h with strength and elongation in middle of the three specimens exhibits the highest fatigue strength of 165 MPa. Considering the effect of yield strength on fatigue strength and fatigue damage, the causes for the parabolic variation of fatigue strength were analyzed.

The nanopowders of Cu2Se were synthesized by the hydrothermal method, and then were hot-pressed into bulk pellets. The effects of different preparation conditions on the structure and thermoelectric properties of Cu2Se nanocrystalline bulk alloys were investigated. The resistivity and Seebeck coefficients increase with the increment of hot-pressing temperatures, while they decrease with the increment of hot-pressing time, except for the Seebeck coefficients of the sample hot-pressed for 30 min. Based on the power factors and dimensionless thermoelectric figure-of-merit (ZT) values, the optimum hot-pressing parameters are 700°C and 30 min.

Purpose: To explore the perceptions of parents regarding the preparation of their children for surgery. Design and methods: A qualitative descriptive study was conducted. Sixteen parents of children who were undergoing various types of elective surgery in a public tertiary hospital in Singapore were recruited. Data were collected through face-to-face interviews and analyzed using thematic analysis. Results: Five themes were derived: (1) assumed roles of the parents; (2) communication, decision-making, and emotional challenges; (3) factors facilitating the preparation of children for surgery; (4) surgery-related and financial concerns; and (5) the desire for more information and better management. While preparing their children for surgery, parents undertook several roles to ensure readiness and to provide support. Parents faced challenges while communicating with their children regarding their surgeries, experiencing negative emotions and dilemmas in making decisions for surgery. Factors such as previous experiences, children’s positive mentality, and access to information helped to facilitate their preparation. Parents expressed surgery-related concerns such as anesthesia and a successful outcome of the surgery, the timing of the surgery, and postoperative care. Parents expressed a desire for easier to understand information through the use of visual materials, and improvements in current practices and management. Conclusion: This study provides a greater understanding of parents’ perceptions of their roles, challenges, influencing factors, concerns, and needs when preparing their children for surgery. Practice implications: The study findings provide insightful aspects for improving current healthcare practices and informing future research studies in exploring better surgery preparation programs for both parents and children.

Continuous blood pressure is measured from various extracranial body sites, with difference in amplitude and phase with intracranial blood pressure. Consequent influences on the accuracy of Windkessel model need further investigation. Between blood pressure and intracranial flow rate, a model with non-linear flow resistance (R-DT) was proposed and compared with the 3-element Windkessel (RCR) model. From the measured blood flow velocity in middle cerebral artery, the blood pressure was estimated by R-DT and RCR models respectively. The parameters in the models were optimized by genetic algorithm. The accuracies of R-DT and RCR models were compared based on their estimation errors to the measured blood pressure. The capacitance element in RCR model indicated limited ability to take the time shift into account. Compared with RCR model, R-DT model had less error (averaged relative error: 5.19% and 2.49% for RCR and RDT models). The non-linear flow resistance was applicable in simulating cerebral arteries.

Lymphaticovenous malformations are rare congenital anomalies leading to oozing, ulceration and recurrent infections. They are managed by a specialist multi-disciplinary team with compression garments, symptomatic treatments and options such as percutaneous sclerotherapy and debulking procedures. Limited literature exists on the use of laser to seal the lymphatic vesicles. We present a 14 years old with a debilitating lymphaticovenous malformation of the hand for whom the risk of amputation was reduced by the use of carbon dioxide laser. Level of evidence: Level V, therapeutic study.

Intensive selection of broilers for improved growth rate is known to exert a negative effect on broiler health, such as an increase in body fat (and its related diseases). Excessive fat deposition in the liver can cause fatty liver hemorrhagic syndrome (FLHS); in addition, traits associated with liver fat have also been associated with FLHS. This study explored the genetic relationships among liver fat-related traits. Data was collected from 462 birds derived from 16th generation Northeast Agricultural University broiler lines divergently selected for abdominal fat content. The body weight at 7 weeks of age (BW7), abdominal fat weight (AFW), abdominal fat percentage, liver fat percentage (LFP), liver weight, and liver percentage were measured. The heritability of these traits and the phenotypic and genetic correlations were estimated, using the restricted maximum likelihood (REML) and Gibbs sampling (GS) methods. The REML and GS methods yielded similar heritability estimates for LFP (0.36 and 0.37, respectively). BW7 showed a high positive genetic correlation with AFW (rA(REML) = 0.74 and rA(GS) = 0.80), and a moderate positive genetic correlation with LFP (rA(REML) = 0.27 and rA(GS) = 0.39). Positive genetic correlations were also observed between AFW and LFP (rA(REML) = 0.35 and rA(GS) = 0.36). These results suggested that selection for growth may increase the AFW and LFP in broilers. LFP is directly related to FLHS; therefore, selection for broiler growth rate may increase the incidence of FLHS.

The effects of obesity on reproduction have been widely reported in humans and mice. The present study was designed to compare the reproductive performance of lean and fat chicken lines, divergently selected for abdominal fat content. The following parameters were determined and analyzed in the two lines: (1) reproductive traits, including age at first egg and total egg numbers from generations 14 to 18, absolute and relative testicular weights at 7, 14, 25, 30, 45 and 56 weeks of age, semen quality at 30, 45 and 56 weeks of age in generation 18, and fertility and hatchability from generations 14 to 18; (2) reproductive hormones at 7, 14, 25, 30, 45 and 56 weeks of age in generation 18; (3) and the relative mRNA abundance of genes involved in reproduction at 7, 14, 25, 30, 45 and 56 weeks of age in generation 18. In females, birds in the lean line laid more eggs from the first egg to 40 weeks of age than the birds in the fat line. In male broilers, the birds in the lean line had higher absolute and relative testicular weights at 7, 14 and 25 weeks of age, but lower absolute and relative testicular weights at 56 weeks of age than the birds in the fat line. Male birds in the lean line had greater sperm concentrations and larger numbers of motile and morphologically normal sperms at 30, 45 and 56 weeks of age than the birds in the fat line. Fertility and hatchability were also higher in the lean line than in the fat line. Significant differences in the plasma levels of reproductive hormones and the expression of reproduction-associated genes were also found at different ages in the lean and fat birds, in both males and females. These results suggest that reproductive performance is better in lean birds than in fat birds. In view of the unique divergent lines used in this study, these results imply that selecting for abdominal fat deposition negatively affects the reproductive performance of birds.

Macrophage migration inhibitory factor (MIF) is a pleiotropic, constitutively expressed, pro-inflammatory cytokine and an important regulator of immune responses. d-dopachrome tautomerase (DDT), a newly described member of the MIF protein superfamily, shares sequence homology and biological activities with MIF. We recently reported that high expression levels of MIF sustain innate immune responses in newborns. Here, we elected to further characterize age-dependent MIF expression and to define whether DDT shares a similar expression profile with MIF. Therefore, we delineated the circulating concentrations of MIF and DDT throughout life using a large cohort of 307 subjects including fetuses, newborns, infants, children, and adults. Compared to levels measured in healthy adults (median: 5.7 ng/ml for MIF and 16.8 ng/ml for DDT), MIF and DDT plasma concentrations were higher in fetuses (median: 48.9 and 29.6 ng/ml), increased further at birth (median: 82.6 and 52.0 ng/ml), reached strikingly elevated levels on postnatal day 4 (median: 109.5 and 121.6 ng/ml), and decreased to adult levels during the first months of life. A strong correlation was observed between MIF and DDT concentrations in all age groups (R = 0.91, P, SCOPUS: ar.j, info:eu-repo/semantics/published

PurposeSome useful bacteria could be used regularly in mycotoxins biodegradation. It is a very good and ecological method, which was tested in experiments when lactobacilli were used. The paper aims to describe this.Design/methodology/approachFive strains of lactobacilli in experiments were shown, by direct enzyme‐linked immunosorbent assay (CD‐ELISA) test after their growth in MRS broth, to have decreased in the amount of deoxynivalenol (DON) measured by spectrophotometer. Free DON in the samples and control is allowed to compete with enzyme‐labeled DON (conjugate) for the antibody binding sites. The test was read in a microwell reader to yield optical densities.FindingsIt was found that Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus fermentum were more active than human strain Lactobacillus casei Shirota.Originality/valueThe paper suggests that other lactobacilli should be tested in this research field and could be used for detoxification of some feed kinds contaminated minimally by DON.

In humans, obesity is associated with increased or decreased levels of serum biochemical indicators. However, the relationship is not as well understood in chickens. Due to long-term intense selection for fast growth rate, modern broilers have the problem of excessive fat deposition, exhibiting biochemical or metabolic changes. In the current study, the Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) were used to identify differences in serum biochemical parameters between the 2 lines. A total of 18 serum biochemical indicators were investigated in the 16th, 17th, and 18th generation populations of NEAUHLF, and the genetic parameters of these serum biochemical indicators were estimated. After analyzing the data from these 3 generations together, the results showed that the levels of 16 of the tested serum biochemical parameters were significantly different between the lean and fat birds. In the fat birds, serum concentrations of high-density lipoprotein cholesterol (HDL-C), HDL-C:low-density lipoprotein cholesterol (LDL-C), total bile acid, total protein, albumin, globulin, aspartate transaminase (AST):alanine transaminase (ALT), γ-glutamyl transpeptidase (GGT), uric acid, and creatinine were very significantly higher (P0.01), whereas LDL-C, albumin:globulin, glucose, AST, ALT, and free fatty acids concentrations in serum were very significantly lower than those in the lean birds (P0.01). Of these 16 serum biochemical parameters, 5 (LDL-C, HDL-C:LDL-C, total bile acid, albumin, and albumin:globulin) had high heritabilities (0.58 ≤ h2 ≤ 0.89), 6 (HDL-C, total protein, globulin, AST:ALT, GGT, and creatinine) had moderate heritabilities (0.29 ≤ h2 ≤ 0.48), and the remaining 5 had low heritabilities (h20.20). Serum HDL-C, HDL-C:LDL-C, and glucose had higher positive genetic correlation coefficients (rg) with abdominal fat traits (0.30 ≤ rg ≤ 0.80), whereas serum globulin, AST, and uric acid showed higher negative genetic correlations with abdominal fat traits (–0.62 ≤ rg ≤ –0.30). The remaining 10 serum biochemical parameters had lower genetic correlations with abdominal fat traits (–0.30rg0.30). In conclusion, we identified serum HDL-C and HDL-C:LDL-C levels as potential biomarkers for selection of lean birds. These findings will also be useful in future studies for investigating obesity and lipid metabolism in humans as well as in other animal species.

In this study, we profiled gene expression in chicken liver and screened differentially expressed genes in the Bai'er layers and fat line broilers. Birds were derived from the 14th generation of Northeast Agricultural University fat broiler lines and Bai'er layers. Chicken genome arrays were used to screen differentially expressed genes in liver tissue from the Bai'er layers and fat line broilers. We screened 671 differentially expressed genes between broilers and layers at the ages of 2 and 4 weeks. We observed enrichment of a series of significant pathways, including the mitogen-activated protein kinase signaling pathway, cell cycle, mammalian target of rapamycin signaling pathway, and p53 signaling pathway. At 2 and 4 weeks, 94 shared differentially expressed genes were observed. We speculated that these genes regulate chicken lipid metabolism.

The aim of this study was to evaluate effects of modified glucomannan (Mycosorb®) on plasma chemistry of broiler chicks after deoxynivalenol (DON) inclusion in the diet from hatching to 6 weeks of age. Three groups of broiler chicks were formed with 14 birds in each group. The three diets included control (0.2 ppm deoxynivalenol), deoxynivalenol-contaminated (3 ppm deoxynivalenol) and deoxynivalenol- contaminated (3 ppm deoxynivalenol) plus Mycosorb®(2 g/kg diet). After 6 weeks of feeding all birds were sacrificed and blood samples for chemical analyses were collected. Serum calcium and alanine aminotransferase activity were significantly elevated and magnesium, total protein, triglycerides and free glycerol were decreased in chicks fed deoxynivalenol-contaminated diet compared with those fed the control diet. Inclusion of Mycosorb®in the diet decreased plasma alkaline phosphatase and alanine aminotransferase activities and reversed plasma levels of magnesium, triglycerides, free glycerol and total protein in chicks induced by dietary deoxynivalenol. Chloride level was not affected by diets. The inclusion of Mycosorb® to DONcontaminated diet, however, did not prevent or alleviate toxic effect on calcium metabolism. Supplementation of modified glucomannan Mycosorb® counteracted most of the plasma parameter alterations caused by deoxynivalenol-contaminated diet in chicks.

Methionine is an essential amino acid in all animal species. Supplementation of appropriate amounts of methionine and analogues to meet requirements is safe for the target species. The use of methionine-based additives will not result in an increased content in tissues and products. Residues present in animal tissues and products resulting from the extremely small quantities of free styrene and 2-vinylpyridine found in DL-methionine copolymer (DL-Met-cop) are very unlikely to raise concerns about consumer safety. None of the products are considered to present a significant inhalation risk. DL-Methionine (DL-Met), DL-Met-cop and DL-methionine protected with ethylcellulose (DL-Met-ec) are non-irritant to skin and eyes, and the lack of sensitisation potential demonstrated for DL-Met is considered relevant to DL-Met-cop and DL-Met-ec. DL-Methionine sodium salt (DL-Met-Na) is considered to be corrosive to skin and eyes. The hydroxy analogue of methionine (HMTBa) is an irritant to the skin and corrosive to the eyes. The calcium salt of HMTBa, HMTBa-Ca, is irritant to the eyes. The absence of dermal sensitation potential demonstrated for HMTBa is considered relevant for HMTBa-Ca. The isopropyl ester of HMTBa, HMTB-i, is non-irritant to skin/eyes, and is not a dermal sensitiser. The use of these products as feed additives does not represent a risk to the environment. DL-Met, DL-Met-Na, HMTBa and HMTBa-Ca are effective dietary sources of methionine for protein synthesis in monogastric animals (including fish). The hydroxy analogues show a somewhat lower bioefficacy than the DL-methionine forms. They can all be used in ruminants, particularly when protected against ruminal degradation by specific formulations. DL-Met-cop, HMTB-i and DL-Met-ec escape ruminal degradation to a certain extent, the remainder being available for gastrointestinal absorption. The FEEDAP Panel does not support the use of the additives under application in water for drinking because of concerns about target animal safety and the maintenance of optimum performance

Urea supplementation to feed for ruminants provides non-protein nitrogen for microbial protein synthesis in the rumen and thus in part replaces other dietary protein sources. Urea supplementation of feed for ruminants at doses up to 1 % of complete feed DM (corresponding to 0.3 g/kg bw/day) is considered safe when given to animals with a well adapted ruminal microbiota and fed diets rich in easily digestible carbohydrates. Based on the metabolic fate of urea in ruminants, the use of urea in ruminant nutrition does not raise any concern for consumers’ safety. Urea is considered to be non irritant to skin and eyes and its topical use suggests that it is not a dermal sensitiser. The risk of exposure by inhalation would be low. The substitution of protein by urea in well balanced feed for ruminants would not result in an increased environmental nitrogen load. Urea is an effective source of non-protein nitrogen substituting for dietary protein in ruminants.

The DEEP site sediment sequence obtained during the ICDP SCOPSCO project at Lake Ohrid was dated using tephrostratigraphic information, cyclostratigraphy, and orbital tuning through marine isotope record. Although this approach is suitable for the generation of a general chronological framework of the long succession, it is insufficient to resolve more detailed paleoclimatological questions, such as leads and lags of climate events between marine and terrestrial records or between different regions. In this paper, we demonstrate how the use of different tie points can affect cyclostratigraphy and orbital tuning for the period between ca. 140 and 70 ka and how the results can be correlated with directly/indirectly radiometrically-dated Mediterranean marine and continental proxy records. The alternative age model obtained shows consistent differences with that proposed by Francke et al. (2015) for the same interval, in particular at the level of the MIS6-5e transition. According to this age model, different proxies from the DEEP site sediment record support an increase of temperatures between glacial to interglacial conditions, which is almost synchronous with a rapid increase in sea surface temperature observed in the western Mediterranean. The results show how important a detailed study of independent chronological tie points is for synchronizing different records and to highlight asynchronisms of climate events.

In the literature on vibration analysis of a coupled vehicle-bridge system, the influence of random undulation of bridge surface has not been fully considered yet. In fact, the response of a vehicle-bridge system depends on both the moving vehicle weight and the bridge undulation. In vibration analysis, the vehicle-bridge system should be taken as a time-variant model, and the response will consist of two parts, namely a deterministic transient one and an evolutionary random one. Based on a unified approach to evolutionary random response problems, suggested by the present authors recently, the coupled response problem of a vehicle-bridge system is studied in detail. Both the deterministic response and the random response of the coupled system are obtained effectively by the Runge-Kutta method. Some qualitative inferences on the acceleration response of the vehicle, the relative response of the suspension, and the flexuous response of the bridge are drawn. Both the method and the results presented here may be helpful in dealing with more complicated practical vibration problems.

This study aimed to investigate gene expression in the chicken liver for lean and fat broiler lines. Birds used in this study were 2 and 4 weeks of age; they were derived from the 14th generation of Northeast Agricultural University broiler lines, which were divergently selected based on abdominal fat content. Chicken Genome Arrays were used to screen differentially expressed genes in the liver tissue from lean and fat birds. At 2 and 4 weeks of age, 770 and 452 genes were differentially expressed between the 2 lines, respectively. The differentially expressed genes were involved in Wnt, insulin signaling, and cell cycle pathways. At 2 and 4 weeks, 42 shared, differentially expressed genes were revealed by the analysis. We speculate that these genes might regulate chicken lipid metabolism.

Butyrate has potent anti-tumorigenic effects on many colon cancer cell lines, including inhibition of growth and promotion of apoptosis in vitro. Nevertheless, despite the butyrate concentration in the colonic lumen being sufficient to result in the death of almost all cells in vitro, colon cancers still develop and grow in vivo, suggesting that cancer cells must develop mechanisms by which they escape the effects of butyrate observed in vitro. Insulin-like growth factor-II (IGF-II) is an autocrine growth factor in many colon cancer cells. The aim of this study was to determine whether IGF-II influences butyrate-mediated apoptosis in LIM 2405 human colon cancer cells. Butyrate and trichostatin A, both of which are histone deacetylase inhibitors although the latter is more specific, induced apoptosis as determined by floating cell counting, Hoechst 33258 staining, DNA laddering and a cell death detection ELISA. IGF-II inhibited the effects of both agents. Butyrate but not trichostatin A also induced LIM 2405 cell migration. In contrast to the above results, IGF-II enhanced butyrate-induced cell migration. Levels of IGF binding protein-3 (IGFBP-3), which may induce apoptosis by IGF-dependent or -independent mechanisms, were increased by butyrate and trichostatin A; IGF-II augmented this effect. It is therefore unlikely that IGFBP-3 mediates butyrate-induced apoptosis. We suggest that IGF-II inhibits the pro-apoptotic effect of butyrate downstream of histone deacetylase inhibition. In contrast, IGF-II promotes histone deacetylase-dependent IGFBP-3 expression and histone deacetylase-independent migration. IGF-II may promote tumour growth by mediating the development of resistance to the pro-apoptotic effects of butyrate.

IGF-II is an autocrine growth factor for many colon cancer cells. This study aimed to determine the role of IGF-II in proliferation and adhesion of LIM 1215 colon cancer cells. RT-PCR demonstrated expression of IGF-I and IGF-II mRNA. Addition of IGF-I or -II increased monolayer proliferation in a dose-dependent manner. Although addition of IGFBP-6 had no effect on basal proliferation, coincubation of IGFBP-6 decreased IGF-II but not IGF-I-induced proliferation. Colony formation in agar was increased by IGF-II, an effect inhibited by coincubation with IGFBP-6. IGFBP-6 alone significantly decreased colony formation. Preincubation of cells with IGF-II increased adhesion to type IV collagen, fibronectin and laminin. IGFBP-6 had no effect on basal cell adhesion but completely inhibited the effects of IGF-II. LIM 1215 colon cancer cells are therefore IGF-responsive but IGF-II is not a major autocrine factor for these cells in monolayer, suggesting heterogeneity between colon carcinoma cell lines with respect to the role of the IGF system.

Encephalitozoonosis is an opportunistic infection in animals and humans. Its clinical form is observed in immunosuppressed hosts. We studied the occurrence of the manifest form of rabbit microsporidiosis under cyclophosphamide immunomodulation in 40 New Zealand rabbits. The experimental animals were intraperitoneally infected with 5 Ã 107Encephalitozoon cuniculispores. Two weeks after infection the animals were treated intraperitoneally with cyclophosphamide, first with 50 mg/kg and then with 15 mg/kg weekly during the 12-week experimental period. Positive controls were eitherE. cuniculi-infected or cyclophosphamide-immunosuppressed animals. The negative control rabbits remained untreated. Both clinical signs of encephalitozoonosis and depression of peripheral blood cell count developed between weeks 4 and 6 in the experimental animals which died during week 6 of the experiment. No clinical signs compatible with encephalitozoonosis were observed in any of the controls. The results suggest that immunosuppression induced by cyclophosphamide can give rise to a lethal form of encephalitozoonosis.

BoldiIarova K., ·. Faix, a. Leng: The Renal Response of Sheep Fed a High Protein Diet to Treatment with Vasopressin Analogue. Acta Vet. Brno 1999, 68: 99-104. This experiment was designed to test whether the long-term formation of highly concentrated urine rises the glomerular filtration rate in sheep like in simple stomach animals. Experiments were carried out on young sheep fed a high protein diet for 3 weeks. In order to produce animals with highly concentrating kidneys, the experimental group was treated with 1-desamino-8-D-arginine vasopressin (dDAVP, Adiuretin-SD, Ferring, Prague). Subcutaneous injections of 12.5 µg dDAVP given twice daily started one week before the measurements of renal function. The clearance protocol showed a decreased urine flow rate (from 3.19 ± 0.50 to 0.33 ± 0.03 ml.min-1, P < 0.001) without changes in glomerular filtration rate (80.18 ± 6.36 vs. 77.86 ± 6.26 ml.min -1 , NS) due to dDAVP. The plasma level of urea was significantly increased (from 5.76 ± 0.39 to 7.28 ± 0.25 mmol.l-1, P < 0.01) concomitantly with the larger renal urea reabsorption (from 239.72 ± 26.16 to 390.53 ± 33.25 µmol.min -1 , P < 0.01) in dDAVP treated group. Both fractional urea excretion (48.44 ± 3.12 vs. 30.33 ± 1.94 %, P < 0.001) and the amount of urea excreted were significantly reduced (206.22 ± 9.04 vs. 170.41 ± 10.76 µmol.min -1 , P < 0.05). One week-lasting treatment with a vasopressin analogue resulted in the decreased urea clearance (from 36.95 ± 2.07 to 23.76 ± 1.97 ml.min -1 , P < 0.001) but it did not influence the osmotic clearance (1.77 ± 0.10 vs. 1.62 ± 0.08 ml.min -1 , NS). In conclusion, the kidneys of sheep do not respond to a long-term formation of highly concentrated urine per se with a rise in the glomerular filtration rate. A possible explanation is that urea recycling through digestive tract of ruminants is of an order of magnitude larger than that in simple stomach animals. Sheep, kidney, GFR, urinary concentrating ability

Summary The predominant insulin-like growth factor binding protein (IGFBP) synthesized by PC12 rat phaeochromocytoma cells is IGFBP-6. Since cAMP agonists regulate IGFBP-6 in other cells, and they may increase neurite outgrowth and catecholaminergic enzyme expression in PC12 cells, we studied regulation of IGFBP-6 by these agents. After 72 h incubation, forskolin and 8-(4-chlorophenylthio)-cAMP (CPT-cAMP) both increased IGFBP-6 protein levels in conditioned media to maximum levels of 231±40 and 275±30%, respectively. Incubation with forskolin resulted in a small, transient rise in IGFBP-6 mRNA levels which was insufficient to account for the increased protein levels. The increased protein levels also could not be altributed to increased cell number, protection of IGFBP-6 from proteolysis or release of IGFBP-6 from a cell-associated reservoir. These findings suggest that increased protein levels may have been due to increased translation of mRNA. Co-incubation of forskolin with dexamethasone (which decreases IGFBP-6 protein and mRNA) demonstrated that the effects of the latter were dominant. The effects of cAMP agonists and IGF-II, which increases IGFBP-6 protein but not mRNA levels, were not inhibited by rapamycin, suggesting that p70 S6 kinase is not involved. The effects of cAMP agonists on IGFBP-6 levels were not directly correlated with neurite outgrowth. These findings extend our knowledge of the molecular basis of the regulation of IGFBP-6 by cAMP agonists, and indicate a novel action of these agents in PC12 cells.

The effects on renal functions of infusing glucagon (100 ng kg-1 min-1) into the portal vein system were studied in young anaesthetized sheep kept on a diet with normal protein and digestible energy contents. The clearance measurements of the left kidney functions showed a decreased urine flow rate (from 0.36 +/ࢤ 0.04 to 0.18 +/ࢤ 0.03 ml min-1; P < 0.01) within the first 10 min of glucagon infusion, falling to 0.07 +/ࢤ 0.02 ml min-1 (P < 0.01) during the next 10 min. The glomerular filtration rate also decreased from 17.56 +/ࢤ 2.92 ml min-1 to its lowest value, 3.34 +/ࢤ 1.02 ml min-1, (P < 0.01) after 20 min of glucagon infusion. Decreases in urea excretion (from 53.1 +/ࢤ 6.46 to 3.82 +/ࢤ 1.27 mumol min-1; P < 0.01) and osmotic clearance (from 0.67 +/ࢤ 0.13 to 0.09 +/ࢤ 0.02 ml min-1; P < 0.01) occurred during the first 20 min. The plasma level of glucose increased from 4.01 +/ࢤ 0.53 to 8.33 +/ࢤ 1.12 mmol l-1 (P < 0.05) 20 min after the start of glucagon infusion. Twenty minutes after the start of glucagon infusion, the values of all the parameters measured began to recover, although they did not reach the control level, even after 1 h. Blood pressure was stable during the whole experiment. The results show that the effects of intraportally infused glucagon on kidney functions in sheep are the opposite of those obtained from similar experiments in laboratory animals with simple stomachs or in humans.

We have directly measured the nonlinear phase shift imposed by control pulses with a range of energies, including higher-order solitons, onto an orthogonally polarized first-order signal soliton via collision in a highly birefringent optical fiber. We find that the signal pulse acquires a collisional phase shift greater than 0.3 π when the pump is a third-order soliton. The experimental results agree closely with analytic and numerical predictions, and lead to the design of a low-latency nonlinear fiber loop demultiplexer.

Renal urea conservation was evaluated in Corriedale ewes during late pregnancy and lactation. Glomerular filtration, renal plasma flow and urea clearance were significantly reduced both states compared with control sheep. Filtered load of urea and urine urea elimination were significantly reduced during lactation (−46% and −45%, respectively, vs. controls). No changes were noted in fractional excretion of urea. Therefore, Corriedale ewes restrict urine urea losses during lactation by reducing glomerular filtration. During late pregnancy, urea sparing is less marked. Key words: Renal functions, urea, pregnancy, lactation, sheep

We demonstrate the routing of optical packets containing an eight-wavelength-division-multiplexing (WDM) channel 10-Gb/s payload through an eight-node subnetwork of the data vortex packet switching fabric. The single-pulse WDM encoding employed for the header and frame bits greatly simplifies the routing control functions and reduces the switching latency. The unique synchronous and distributed control mechanism eliminates the requirement of optical buffering and avoids packet contention. We demonstrate the virtual buffering capability of the switching fabric through a cascade of seven node hops, achieving a power penalty of less than 1.5 dB for each of the eight payload channels.