Dryopteris filix-mas (Dryopteridaceae) leaves inhibit mouse uterine activity

Background: The plant Dryopteris filix-mas has been used traditionally for its uterine-stimulant effects. Aim: The current study is therefore aimed at investigating and determining the effect of the leaves of D. filix-mas on uterine contractility in vitro.Setting: Fresh leaves of D. filix-mas were collected from a river bank in the south-western part of Nigeria.Methods: The leaves of D. filix-mas were cleaned, dried and extracted in methanol. The extract (0.07 µg/mL–21.0 µg/mL) was tested on the isolated mouse uteri in order to determine activity on spontaneous-induced uterine contractions. Subsequently the extract (0.005 mg/mL and 0.05 mg/mL) was tested on oxytocin-induced contraction (0.00017 ng/mL–4.98 ng/mL) in calcium-containing media, submaximal oxytocin-induced contraction (0.116 ng/mL) in calcium-free media and in the presence of high KCl-induced uterine contractions (80 mM). The extract was also subjected to mass spectrometric determination of secondary metabolites.Results: The plant extract inhibited spontaneous-induced contractions with IC50 amplitude = 658.41 ng/mL ± 0.11 ng/mL and IC50 frequency = 175.32 ng/mL ± 0.53 ng/mL. The plant extract inhibited oxytocin-induced and high KCl-induced uterine contractions (p < 0.01 at 0.5 mg/mL). The plant extract had no effect on oxytocin-induced contractions under calcium-free conditions. Secondary metabolites belonging to classes of fatty acids, alkaloids, saponin glycosides, amino acids, limonoids, terpenes and porphyrins were identified.Conclusion: The current study reports an inhibitory effect of the plant on uterine contractility in this study, suggesting possible application as a tocolytic or as a contraceptive, as most contraceptive plants have shown uterine-relaxing effect

On compactoid and limited sets in non-Archimedean locally convex spaces

In [2] and [3] spaces in which every bounded subset is a compactoid was studied. Every compactoid set is limited but the converse is not true [3]. In this paper, we shall study some spaces in which every limited set is compactoid. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 571-57

An application of the extended RSA congruence

In [4], we proved that the RSA congruence could be extended to a situation where the modulus of the congruence is a simple product of primes. In this work, we discuss the cryptosystem of this extended RSA congruence as an analogue of the RSA cryptosystem, which is hereafter referred to as the Extended RSA Cryptosystem.Journal of the Nigerian Association of Mathematical Physics Vol. 8 2004: pp. 341-34

Microbial Flora of Smoke-Dried Catfish (Clarias Gariepinus) Processed and Sold in Some Abattoirs in Bayelsa and Rivers States

The microflora of smoked catfish (Clarias gariepinus) sold in some abattoirs in Bayelsa and Rivers States were investigated. Smoked catfish samples were purchased within abattoirs and aseptically transported in ice-packed coolers to the laboratory. The total heterotrophic bacteria, total coliform, total hydrocarbon utilizing bacteria, total fungi and hydrocarbon utilizing fungal counts and identification of isolates from samples were analyzed using standard microbiological methods. Mean values of counts obtained showed that total heterotrophic bacteria ranged from 5.4 × 106CFU/g to 4.0 × 105CFU/g, total hydrocarbon utilizing bacteria ranged from 1.5 × 104 to 1.0 × 103CFU/g, total coliform ranged from 1.7 × 106CFU/g to 0, total fungi ranged from 4.3 × 104 CFU/g to 1.2 × 104CFU/g and total hydrocarbon utilizing fungi ranged from 3.5 × 103CFU/g to 1.1 × 103CFU/g. Kruskal Walis H test showed no significant differences (P≤0.05) in the total heterotrophic bacterial load nor in the total fungal load in the locations. Bacteria identified are Bacillus sp, Enterobacter sp, Escherichia coli, Micrococcus sp, Pseudomonas sp, Salmonella sp., and Shigella species. Bacillus sp, Pseudomonas sp and Micrococcus sp., were isolated in all the samples. Salmonella sp and Shigella sp occurred in Igbogene and Swale samples. Bacillus sp recorded the highest occurrence (34%) while Enterobacter sp. and Micrococcus sp recorded the least (7%). Bacteria with hydrocarbon utilizing potentials with percentage occurrence were Bacillus sp (70%) and Pseudomonas sp (30%). Fungi isolated were Aspergillus niger, A. flavus, Aspergillus fumigatus, Penicillium sp, Fusarium sp., and Rhizopus sp. Aspergillus species recorded the highest frequency (36.0%) while Rhizopus sp recorded the least (9.83%). Aspergillus niger, Fusarium sp and Penicillium sp were isolated from all the samples. Penicillium sp recorded hydrocarbon utilizing the potential and the highest percentage of occurrence (35.89%). The presence of a high microbial load of pathogenic bacteria and known mycotoxin producing fungi in the smoke-dried catfish are of great public health significance.</jats:p

A software for the RSA Encription

In Omokaro 2003[12], we extended the RSA Congruence to a finite number of primes. The extended RSA Cryptosystem was later obtained in Omokaro 2004[13] as an analogue of the RSA Cryptosystem to obtain the extended RSA Cryptosystem. In this work we provide a software for the enciphering of data in RSA cryptosystem Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 423-43

Microflora population in mangrove sediments of Cross River estuary

No Abstract.Global Journal of Pure and Applied Sciences Vol. 13 (3) 2007: pp.347-35

Enrichment of Hematopoietic Stem Cells from Normal and Trp53 Null Mice Using SLAM Receptor CD150 as a Positive Selection Marker.

Abstract CD150 is a member of the signaling lymphocyte activation molecule (SLAM) family of receptors which can be used as a positive selection marker for hematopoietic stem cells (HSCs) from mouse bone marrow (BM) and fetal liver (Kiel et al., Cell 2005; Yilmaz et al., Blood 2006; Kim et al., Blood 2006). In the current study, we combined CD150 with a set of lineage-specific markers to enrich HSCs, comparing normal C57BL/6 (B6) mice with B6-Trp53-deficient (Trp53 null) mice which were previously shown to have elevated HSC activity. Using an anti-mouse CD150 antibody (Clone TC 15-12F 12.2, BioLegend), we defined a population of Lin−CD41−CD48−CD150+(SLAM) cells that is 0.0078 ± 0.0010% and 0.0135 ± 0.0010% of total BM cells from B6 and Trp53 null mice. The size of the SLAM cell fraction was strongly correlated (R2= 0.7116, P&amp;lt;0.0013) to the population of well defined Lin−Sca1+CD117+ (LSK) cells (at 0.0165 ± 0.0036% and 0.0276 ± 0.0036% respectively) for the same B6 and Trp53 null mice we have tested (results consistent with previous findings indicating that the HSC pool is larger in Trp53 null mice than in B6 mice). To test HSC function in vivo, we sorted SLAM cells and Lin−CD41−CD48−CD150+ (SLAM−) cells from B6 and Trp53 null donors and transplanted them into lethally irradiated (11 Gys) B6 recipients. In a day 12 colony forming unit-spleen (CFU-S) assay, both SLAM and SLAM−cells formed colonies but the SLAM cells contained 12–15 fold higher day 12 CFU-S than did SLAM−cells. In a competitive repopulation assay, when donor SLAM and SLAM−cells were mixed with fresh B6-CD45.1 BM cells and engrafted into lethally-irradiated B6 recipients for six months, the density of repopulating units (RUs) was 22.48 ± 12.05 and 11.06 ± 8.78 per thousand SLAM cells from B6 and Trp53 null donors, dramatically higher than the RU density of 0.43 ± 0.09 and 0.55 ± 0.43 per thousand SLAM−cells from the same B6 and Trp53 null donors. When BM cells from the competitive repopulation recipients were serially-transplanted into secondary recipients, the SLAM donor cell contribution increased while the SLAM−donor cell contribution decreased with time when measured at two, six and fourteen weeks in the secondary recipients, indicating that SLAM cells were the primitive HSCs that sustained hematopoiesis long-term. No recipient that received Try53 null SLAM or SLAM−cells died, significantly different from our previous observation that whole BM cells from Trp53 null donors yielded high donor reconstitution in a competitive repopulation assay but 56% recipient died within five months after reconstitution (TeKippe et al., Exp Hematol 2003). SLAM markers may have enriched HSCs by excluding any Try53 null BM cell responsible for early recipient death. Analysis of intracellular reactive oxygen species (ROS) revealed higher proportions of ROS−cells in the CD150+ than in the CD150− BM cell fraction in both B6 and Trp53 null mice, consistent with the hypothesis that HSCs are metabolically inactive and therefore contain lower level of ROS. While SLAM− cells may still contain some residual HSC activity, results from the present study are in strong support of utilization of SLAM receptor CD150 as a positive selection marker for HSCs. The Lin− CD41−CD48−CD150+SLAM combination provides a simple and effective method for HSC enrichment.</jats:p

Fas- and Fas Ligand Rather Than Perforin-Mediated Apoptosis Has a Dominant Role in Target Cell Death in Murine Models of Immune- Mediated Bone Marrow Failure

Abstract Fas-Fas ligand and perforin-granzyme are two important cell death pathways associated with cytotoxic T cell induced target cell apoptosis. In patients with immune-mediated aplastic anemia, the development of bone marrow (BM) failure is associated with up-regulation in Fas ligand expression on effector cytotoxic T cells and elevated Fas expression on target BM cells. In some aplastic anemia patients, peripheral blood T lymphocytes also carry polymorphisms in the perforin gene which have been associated with familial hemophagocytosis. These findings suggested that Fas ligand/Fas might be the key signaling molecules mediating cell destruction while perforin might also play a role in the development of BM failure in patients with aplastic anemia. We have modeled immune-mediated BM failure in the mouse by infusing allogeneic lymph node (LN) cells from C57BL/6 (B6) donors into sublethally-irradiated CByB6F1 and C.B10 recipients that are mismatched at either major histocompatibility (MHC) or minor histocompatibility (minor-H) loci. Expansion and activation of allogeneic T cells results in increased production of the inflammatory cytokines gamma interferon and tissue necrosis factor alpha in recipient BM, massive BM cell destruction, severe marrow hypoplasia, and fatal pancytopenia. In the current study, we directly tested the roles of Fas, Fas ligand and perforin in the development of BM failure by using murine models with spontaneous mutations at the lymphoproliferation (lpr) and generalized lymphoproliferative disease (gld) loci, or with germline deletion of the gene perforin (prf−/−). Fas and Fas ligand-deficient lpr and gld mutant mice had no evidence of hematopoietic deficiency despite their autoimmune environment and marked lymphoproliferation. LN cells from lpr and gld mice caused significantly less apoptosis to minor-H mismatched C.B10 BM cells when co-cultured in a cytotoxicity assay in vitro, in comparison to LN cells from wild-type B6 mice. Infusion of lpr, gld, and B6 donor LN cells into sub-lethally irradiated CB10 recipients all caused massive T cell expansion in recipient BM with high level expression of CD11a, indicative of T cell activation, but only B6 LN cells caused severe BM destruction. In contrast, recipients of lpr and gld LN cells had only mild to moderate pancytopenia and marrow hypocellularity. We inferred from these results that disruption of the Fas ligand/Fas signaling pathway effectively abrogated immune mediated marrow destruction. To test the role of perforin in BM failure, we first analyzed prf−/−- mice and found no obvious change in cellular composition in lymphohematopoietic tissues in comparison to wild-type B6 controls. LN cells from prf−/− mice showed reduced ability to induce C.B10 BM cell apoptosis in an in vitro cytotoxicity assay when compared to wild-type B6 LN cells. Infusion of 5–10 million prf−/− LN cells into CByB6F1 and C.B10 recipients produced obvious BM failure in both recipient types with pancytopenia and marrow hypoplasia about 80–90% as severe as in control recipients of 5 million B6 LN cells. In both CByB6F1 and C.B10 recipients, infused prf−/− LN cells resulted in less T cell expansion, a similar level of T cell activation, higher proportions of T cells containing gamma-interferon and tissue necrosis factor-alpha, and a higher proportion of T cells expressing the Fas ligand CD178, in comparison to the infused B6 LN cells. We conclude that Fas-Fas ligand-mediated transmembrane signaling provides the major cell death pathway, while perforin-granzyme-mediated exocytosis plays a minor role, in BM cell destruction in animal models of immune-mediated BM failure.</jats:p