Cytology of the spleen.

Fine-needle aspiration of the spleen is a useful method for evaluation of reactive, inflammatory, and neoplastic disorders, particularly those that involve the hematopoietic system. Interpretation of splenic aspirates is enhanced by concurrent evaluation of blood and other hemic tissues.     

Identification and characterization of topoisomerase II inhibitory peptides from soy protein hydrolysates

Topoisomerases are targets of several anticancer agents because their inhibition impedes the processes of cell proliferation and differentiation in carcinogenesis. With very limited information available on the inhibitory activities of peptides derived from dietary proteins, the objectives of this study were to employ co-immunoprecipitation to identify inhibitory peptides in soy protein hydrolysates in a single step and to investigate their molecular interactions with topoisomerase II. For this, soy protein isolates were subjected to simulated gastrointestinal digestion with pepsin and pancreatin, and the human topoisomerase II inhibitory peptides were co-immunoprecipitated and identified on a CapLC- Micromass Q-TOF Ultima API system. The inhibitory activity of these peptides from soy isolates toward topoisomerase II was confirmed using three synthetic peptides, FEITPEKNPQ, IETWNPNNKP,and VFDGEL, which have IC 50 values of 2.4, 4.0, and 7.9 mM, respectively. The molecular interactions of these peptides evaluated by molecular docking revealed interaction energies with the topoisomerase II C-terminal domain (CTD) (-186 to -398 kcal/mol) that were smaller than for the ATPase domain (-169 to -357 kcal/mol) and that correlated well with our experimental IC 50 values ( R (2) = 0.99). In conclusion, three peptides released from in vitro gastrointestinal enzyme digestion of soy proteins inhibited human topoisomerase II activity through binding to the active site of the CTD domain.     

Distribution of tissue enzymes in three species of pinnipeds.

In domestic animal medicine, changes in serum enzyme levels are routinely used as diagnostic tools to detect liver disease. Hepatic disease occurs in pinnipeds, but limited data are available on the tissue distribution of serum enzymes in marine mammals. The objectives of this study were to determine the tissue distribution of seven serum enzymes in three pinniped species. Enzymes evaluated were alanine aminotransferase (ALT), aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), creatine kinase (CK), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) in tissues from California sea lions (Zalophus californianus) (n = 5), harbor seals (Phoca vitulina) (n = 5), and northern elephant seals (Mirounga angustirostris) (n = 5) that stranded and then died at a rehabilitation center. Samples were evaluated in duplicate from liver, skeletal muscle, cardiac muscle, kidney, adrenal, spleen, pancreas, lung, lymph node, and intestine. Patterns of tissue enzyme distribution were similar in all species, with SDH activity highest in liver and kidney, CK activity highest in skeletal and cardiac muscle, ALP activity highest in adrenal, and GGT activity highest in the kidney. Aspartate aminotransferase and LDH activities were less specific, with high activity in multiple tissues. Tissue ALT activity was high in the liver of all species, but was also high in cardiac muscle (California sea lions), skeletal muscle (harbor seals), and kidney (elephant seals). These results suggest that concurrent analysis of SDH, ALT, and CK would provide high specificity and sensitivity for the detection of hepatic lesions, and allow differentiation of liver from skeletal muscle lesions in pinniped species.     

Catalytic inhibition of human DNA topoisomerase II by interactions of grape cell culture polyphenols

Previously, we isolated mixed polyphenolic fractions on a toyopearl matrix (TP-2 to TP-6) from grape cell cultures that were highly potent catalytic inhibitors in a human DNA topoisomerase II assay for cancer chemoprevention. The objectives of this study were to evaluate the potency of, and potential interactions between, individual fractions and some of the purified bioactive polyphenols that comprise these fractions on human DNA topoisomerase II catalytic activity. Treatments that combined anthocyanin-rich fractions (TP-2; 0.5 or 2.0 microg of dried material/mL), fractions containing catechins, procyanidin dimers, and flavanones (TP-4; 0.25 microg of dried material/mL), and/or fractions enriched with procyanidin oligomers and polymers (TP-6; 0.15 or 0.5 microg of dried material/mL) showed additive effects toward catalytic inhibition of the enzyme. Epicatechin gallate (IC50 = 0.029 microM), myricetin (0.39 microM), procyanidin B2 (PB2, 4.5 microM), and resveratrol (65.7 microM), constituents of the most bioactive mixed fraction from grape cell culture (TP-4), each individually provided potent catalytic inhibition of topoisomerase II. In addition, potentiating interactions between the PB2 and the other polyphenolic constituents mentioned above and between myricetin and resveratrol were clearly demonstrated. A synergistic interaction between myricetin and resveratrol was also confirmed with isobolographic analysis at a molar ratio of 1:70.     

Greater sage-grouse as an umbrella species for sagebrush-associated vertebrates

Widespread degradation of the sagebrush ecosystem in the western United States, including the invasion of cheatgrass, has prompted resource managers to consider a variety of approaches to restore and conserve habitats for sagebrush-associated species. One such approach involves the use of greater sage-grouse, a species of prominent conservation interest, as an umbrella species. This shortcut approach assumes that managing habitats to conserve sage-grouse will simultaneously benefit other species of conservation concern. The efficacy of using sage-grouse as an umbrella species for conservation management, however, has not been fully evaluated. We tested that concept by comparing: (1) commonality in land-cover associations, and (2) spatial overlap in habitats between sage-grouse and 39 other sagebrush-associated vertebrate species of conservation concern in the Great Basin ecoregion. Overlap in species’ land-cover associations with those of sage-grouse, based on the ? (phi) correlation coefficient, was substantially greater for sagebrush obligates than non-obligates . Spatial overlap between habitats of target species and those associated with sage-grouse was low (mean ? = 0.23), but somewhat greater for habitats at high risk of displacement by cheatgrass (mean ? = 0.33). Based on our criteria, management of sage-grouse habitats likely would offer relatively high conservation coverage for sagebrush obligates such as pygmy rabbit (mean ? = 0.84), but far less for other species we addressed, such as lark sparrow (mean ? = 0.09), largely due to lack of commonality in land-cover affinity and geographic ranges of these species and sage-grouse.     

Transgenic overexpression of expansin influences particle size distribution and improves viscosity of tomato juice and paste

Suppression of the expression of a ripening-related expansin gene, LeExp1, in tomato enhanced fruit firmness and overexpression of LeExp1 resulted in increased fruit softening. Because of the incompletely understood relationship between fresh fruit texture and the consistency of processed products, we examined the effects of LeExp1 overexpression on the processing characteristics of tomato fruit. As determined by Bostwick consistency and by controlled strain rheometry, juices and pastes prepared from transgenic tomatoes with suppressed LeExp1 expression had a higher viscosity than preparations from control fruits. However, the viscosity of juice and paste prepared from fruit overexpressing LeExp1 was significantly greater than products from controls or lines with reduced LeExp1. Bostwick consistency increased by 9% (juice) and 6% (paste) in lines with suppressed LeExp1 expression but increased by 27.5% (juice) and 19.5% (paste) in lines overexpressing LeExp1, relative to controls. Determined by laser diffraction, the particles in juice and paste prepared from transgenic fruits with reduced LeExp1 expression were smaller, and preparations from fruits overexpressing LeExp1 had a size distribution indicating more large particles. Analysis of cell wall polysaccharides size indicated that LeExp1 overexpression enhanced depolymerization of water soluble pectins as well as tightly bound matrix glycans. LeExp1 overexpression may allow increased cell wall hydration, resulting in expanded particle size and increased viscosity of products. Because either LeExp1 suppression or overexpression leads to improved consistency, the interactions that contribute to optimal product rheological properties are complex.     

The cation denudation rate as a quantitative index of sensitivity of eastern Canadian rivers to acidic atmospheric precipitation

A model has been developed that relates the cation denudation rate (CDR) of a watershed (the rate that cations derived from chemical weathering are carried off by runoff), the atmospheric load of excess SO₄, and the pH of the river. Chemical and discharge data for rivers in Nova Scotia and Newfoundland were used to develop and test the model, which is based upon the common major ion chemistry of soft surface waters, and may be expressed by three statements: (1) CDR (meq m^?2 yr^?1) ? Excess SO₄ ^?? load (meq m^?2 yr^?1) = HCO₃ ^? (meq m^?2 yr^?1), (2) HCO₃ ^? (meq m^?2 yr^?1)/Runoff (m³ m^?2 yr^?1) = HCO₃ ^? (meq m^?3), (3) pH = pK + \(pP_{CO_2 } \) ? pHCO₃ ^?. The model in concentration form applies well to lakes. A detailed analysis of the data for the Isle aux Morts River, Newfoundland, is presented, showing that the CDR varies throughout the year, affected by both discharge and seasonal pattern.     

Isolation of radiolabeled isoflavones from kudzu (Pueraria lobata) root cultures

Isoflavones have potential for preventing and treating several chronic health conditions, such as osteoporosis, cardiovascular disease, and cancer. In this study, radiolabeled isoflavones were recovered from kudzu (Pueraria lobata) root cultures after incubation with uniformly labeled (14)C-sucrose in the culture medium for 21 days. Approximately 19% of administered label was recovered in the isoflavone-rich dried extracts of kudzu root cultures (90.2 microCi/g or 3.3 MBq/g extract). HPLC-PDA analysis revealed the predominant isoflavones isolated from kudzu root cultures to be puerarin, daidzin, and malonyl-daidzin. The average concentration of the major isoflavone puerarin in kudzu root cultures was 33.6 mg/g extract, with a specific activity of 63.5 microCi/g (2.3 MBq/g). The isolated isoflavones were sufficiently (14)C-labeled to permit utilization for subsequent in vivo metabolic tracking studies.     

Effects of social network factors on information acquisition and adoption of improved groundnut varieties: the case of Uganda and Kenya

Social networks play a significant role in learning and thus in farmers’ adoption of new agricultural technologies. This study examined the effects of social network factors on information acquisition and adoption of new seed varieties among groundnut farmers in Uganda and Kenya. The data were generated through face-to-face interviews from a random sample of 461 farmers, 232 in Uganda and 229 in Kenya. To assess these effects two alternative econometric models were used: a seemingly unrelated bivariate probit (SUBP) model and a recursive bivariate probit (RBP) model. The statistical evaluation of the SUBP shows that information acquisition and adoption decisions are interrelated while tests for the RBP do not support this latter model. Therefore, the analysis is based on the results obtained from the SUBP. These results reveal that social network factors, particularly weak ties with external support (e.g., researchers, extension agents, etc.), partially influence information acquisition, but do not influence adoption. In Uganda, external support, gender, farm size, and geographic location have an impact on information acquisition. In Kenya, external support and geographic location also have an impact on information acquisition. With regard to adoption, gender, household size, and geographic location play the most important roles for Ugandan farmers, while in Kenya information from external sources, education, and farm size affect adoption choice. The study provides insight on the importance of external weak ties in groundnut farming, and a need to understand regional differences along gender lines while developing agricultural strategies. This study further illustrates the importance of farmer participation in applied technology research and the impact of social interactions among farmers and external agents.