Effects of Addition of Tissue‐Type Plasminogen Activator in In Vitro Fertilization Medium on Bovine Embryo Development and Quality

Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue‐type plasminogen activator (t‐PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus‐oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t‐PA and/or its inhibitor epsilon‐aminocaproic acid (control, t‐PA, t‐PA+ε‐ACA, ε‐ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t‐PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε‐ACA. PAA in the treated group was significantly reduced by ε‐ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t‐PA‐modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t‐PA. In conclusion, it appears that excessive t‐PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.     

Detecting interaction(s) and assessing the impact of component subsets in a chemical mixture using fixed-ratio mixture ray designs

An important environmental and regulatory issue is the protection of human health from potential adverse effects of cumulative exposure to multiple chemicals. Earlier literature suggested restricting inference to specific fixed-ratio rays of interest. Based on appropriate definitions of additivity, single chemical data are used to predict the relationship among the chemicals under the zero-interaction case. Parametric comparisons between the additivity model and the model fit along the fixed-ratio ray(s) are used to detect departure from additivity. Collection of data along reduced fixed-ratio rays, where subsets of chemicals of interest are removed from the mixture and the remaining compounds are at the same relative ratios as considered in the full ray, allow researchers to make inference about the effect of the removed chemicals. Methods for fitting simultaneous confidence bands about the difference between the best fitting model and the model predicted under additivity are developed to identify regions along the rays where significant interactions occur. This general approach is termed the “single chemicals required” (SCR) method of analysis. A second approach, termed “single chemicals not required” (SCNR) method of analysis, is based on underlying assumptions about the parameterization of the response surface. Under general assumptions, polynomial terms for models fit along fixed-ratio rays are associated with interaction terms. Consideration is given to the case where only data along the mixture rays are available. Tests of hypotheses, which consider interactions due to subsets of chemicals, are also developed.     

Soy ingredients stabilize bread dough during frozen storage

Bread with 48.5% soy ingredients was assessed for quality during frozen storage of the dough. Soy protein was hypothesized to prevent water migration during frozen storage, thereby producing dough that would exhibit fewer structural changes than traditional wheat bread. Wheat and soy bread were baked from dough that was fresh or frozen (−20 °C, 2 or 4 wks). Dough and bread were assessed for physical properties including moisture content, percent “freezable” and “unfreezable” water, dough extensibility, and bread texture. The bread was subjected to an untrained sensory panel. The soy bread was denser, chewier, and had a higher moisture content than wheat bread. When baked from fresh or frozen dough, soy bread was rated “moderately acceptable” or higher by 70% of panelists. Soy minimized changes in dough extensibility and resistive force to extension, leading to minimal changes in bread hardness. Although consumers could distinguish between bread baked from soy dough that was fresh or frozen for 4 wks, sensorial and textural data suggested that the rate at which the quality of the soy dough deteriorated was slower than that of wheat dough. In conclusion, the dough of consumer-acceptable soy bread retained quality characteristics during frozen storage slightly better than wheat dough.     

Distribution of Redox Enzymes in Millstreams and Relationships to Chemical and Baking Properties of Flour

Millstream flours, bran, pollard, and germ fractions were prepared from two Australian and two New Zealand wheat cultivars using a pilot‐scale roller mill. The distribution of six redox enzymes in milling fractions and the relationship of the enzymes to baking parameters were investigated. Lipoxygenase (LOX), dehydroascorbate reductase (DAR), and protein disulfide isomerase (PDI) tended to be higher in the tail‐end fractions of break and reduction flour streams, but the highest levels were in the bran, pollard, and germ fractions. These enzymes had moderate to strong correlations with ash content of flour. These results indicated that a considerable amount of these enzymes in the tail‐end flour streams were likely to be derived from contamination with bran, aleurone, or germ components of grain. Peroxidase (POX) tended to be higher in the break flours, but polyphenol oxidase (PPO) and ascorbate oxidase (AOX) tended to be evenly distributed in the millstream flours. These three enzymes generally had poor correlations with ash and baking parameters. LOX and DAR had a negative correlation with the baking quality of bread made in the absence of ascorbic acid (AA) but a poor correlation with improvement of bread quality made with AA. The negative correlation probably reflects the high content of ash (hence trichomes), glutathione, and protein thiols in those fractions that have high LOX and DAR, and these high‐reducing‐power components and trichomes in flour may be the actual cause of poor quality bread. PDI generally had a poor correlation with bread quality in the absence of AA but a significant positive correlation with improvement in the quality of bread made with AA. It thus seems that the endogenous levels of these six enzymes were not a limiting factor in the breadmaking process, except for PDI, the levels of which may have positively influenced breadmaking in the presence of AA.     

Distribution of Glutathione in Millstreams and Relationships to Chemical and Baking Properties of Flour

Fourteen millstream flours, a straight‐run flour, bran, pollard, and germ were prepared separately from two Australian and two New Zealand wheat cultivars using a 650 kg/hr pilot roller mill. Glutathione (GSH) and oxidized glutathione (GSSG) were measured in all samples. The Australian cultivars had higher levels of GSH and GSSG than the New Zealand cultivars, and in all cultivars the levels in pollard and germ were considerably higher than in flour samples. Generally, the early break flours and early reduction flours had lower GSSH/GSSG levels than the tail‐end break and reduction flours. There was a strong correlation between GSH/GSSG and ash content in millstream flours, which indicated that much of the GSH/GSSG in the flour was likely to have derived from contamination by bran, aleurone (pollard), and germ. There were also moderate to strong correlations between GSH/GSSG and the cysteine content of all proteins in flour. GSH/GSSG correlated strongly with the albumin and globulin content of flour but not with gliadin and glutenin. The volume and crumb texture properties of bread made with millstream flours in the absence of ascorbic acid (AA) were negatively correlated with GSH/GSSG. The change in bread volume and texture properties when AA was added to dough (baking improver effect of AA), however, were poorly correlated with GSH/GSSG.     

Treatment of right dorsal ulcerative colitis in a horse

Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right lateral approach at the 16th rib resulted in resolution of intestinal protein loss and colic. The results of this case suggest that surgical resection of the ulcerated right dorsal colon may be the recommended treatment for right dorsal ulcerative colitis.     

Analysis based on RAPD and ISSR Markers Reveals Closer Similarities among <Emphasis Type="Italic">Citrullus</Emphasis> and <Emphasis Type="Italic"> Cucumis</Emphasis> Species than with <Emphasis Type="Italic">Praecitrullus fistulosus</Emphasis> (Stocks) Pangalo

A cucurbit species named Praecitrullus fistulosus (Stocks) Pangalo, which thrives in India, is considered to be a distant relative of watermelon. Recent experiments indicated that it has mild resistance to whiteflies (Bemisia tabaci). However, our attempts to cross various US plant introductions (PIs) of P. fistulosus with watermelon or other Citrullus PIs have not been successful. Thus, to determine genetic relatedness among those species, phylogenetic analysis [based on simple sequence repeat (SSR)–anchored (also termed ISSR), and randomly amplified polymorphic DNA (RAPD) markers] was conducted among PIs of P. fistulosus, Citrullus lanatus var. lanatus (watermelon), C. lanatus var. citroides and the wild Citrullus colocynthis. Phylogenetic relationships were also examined with Cucumis melo (melon), Cucumis sativus (cucumber), and wild Cucumis species including C. africanus, C. metuliferus, C. anguria, C. meeusei, and C. zeyheri. Wide genetic distance exists between Citrullus and Cucumis groups (8% genetic similarity). Phylogenetic relationships among Citrullus species and subspecies are closer (25–55% genetic similarity) as compared with those among most Cucumis species (14–68% genetic similarity). P. fistulosus appeared to be distant from both Cucumis and Citrullus species (genetic similarity between P. fistulosus and Cucumis or Citrullus groups is less than 3%). Although wide genetic differences and reproductive barriers exist among cucurbit species examined in this study, they are still considered as potential germplasm source for enhancing watermelon and melon crops using traditional breeding and biotechnology procedures.     

Potato responses to calcium application on several soil types

On low cation exchange capacity, sandy soils where soil test Ca is low, potato tuber (Solanum tuberosum L.) Ca levels may not be optimal for maximum yield or quality; therefore, this study evaluated the effect of several levels of applied Ca on potato yield and quality on four soil types in Wisconsin. Calcium was applied to a Plainfield loamy sand, a Keiner loamy sand, a Pence sandy loam, and an Antigo silt loam at five rates in 1984 (0, 84, 252, 420, and 588 kg Ca ha^?1) and at six rates in 1985 (0, 56, 112, 168, 224, and 336 kg Ca ha^?1) as a band of CaSO₄ in the hill. In 1984, on the Plainfield soil, three rates of sidedress Ca(NO₃)₂ (0, 84, and 168 kg Ca ha_?1) were factorially combined with the five CaSO₄ treatments to evaluate the efficacy of Ca(NO₃)₂ as a concomitant Ca and N source. In general, total yield was not affected by CaSO₄ additions; however, the addition of approximately 100 kg Ca ha^?1 as Ca(NO₃)₂ increased total yield 3.6 Mg ha^?1. On the low-CEC, low-Ca soils (Plainfield and Kelner), improved tuber grade and/ or US1A size grade were detected with the addition of up to approximately 300 kg Ca ha^?1 as CaSO₄. The percent of US1A tubers increased 5 to 10% and the yield of US1A prime size (170–370 g) tubers increased 3.4 to 8.4 Mg ha^?1 above control values. These improvements were accompanied by increased periderm Ca concentrations, even though leaflet Ca concentrations were not affected by Ca applications. The use of 100 kg Ca ha^?1 asCa(NO₃)₂ in combination with CaSO₄ was more effective than CaSO₄ alone. On higher soil test Ca soils (Pence and Antigo), responses were inconsistent and periderm Ca was generally not increased.