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In the present paper, we initiate the study of ∗-η-Ricci soliton within the framework of Kenmotsu manifolds as a characterization of Einstein metrics. Here we display that a Kenmotsu metric as a ∗-η-Ricci soliton is Einstein metric if the soliton vector field is contact. Further, we have developed the characterization of the Kenmotsu manifold or the nature of the potential vector field when the manifold satisfies gradient almost ∗-η-Ricci soliton. Next, we deliberate ∗-η-Ricci soliton admitting (κ,μ)′-almost Kenmotsu manifold and proved that the manifold is Ricci flat and is locally isometric to Hn+1(-4)×Rn. Finally we present some examples to decorate the existence of ∗-η-Ricci soliton, gradient almost ∗-η-Ricci soliton on Kenmotsu manifold.

In this paper, we present the general notion of quasi hemi-slant submanifolds of metallic Riemannian manifolds. We study some properties of submanifolds, specially quasi hemi-slant submanifolds of metallic and golden Riemannian manifolds. We obtain some necessary and sufficient conditions for submanifolds to be quasi hemi-slant in metallic and golden Riemannian manifolds and also obtain integrability conditions for the distributions. At last, we construct an example of a quasi hemi-slant submanifold of a metallic Riemannian manifold.

In the present paper we study characterizations of odd and even dimensional N(k)-mixed quasi-Einstein manifold and finally prove that a N(k)-mixed quasi-Einstein manifold is a semi mixed quasi-Einstein manifold under a certain condi-tion. Key words : N(k)-mixed quasi Einstein manifold, semi mixed-Einstein manifold., 1. Introduction A Riemannian manifold (M, g) with dimension (n [greater than or equal to] 2) is said to be an Einstein manifold if the Ricci tensor satisfies the condition [...]

We study conformal η-Einstein solitons on the framework of trans-Sasakian manifold in dimension three. Existence of conformal η-Einstein solitons on trans-Sasakian manifold is discussed. Then we find some results on trans-Sasakian manifold which are conformal η-Einstein solitons where the Ricci tensor is cyclic parallel and Codazzi type. We also consider some curvature conditions with addition to conformal η-Einstein solitons on trans-Sasakian manifold. We also use torse-forming vector fields in addition to conformal η-Einstein solitons on trans-Sasakian manifold. Finally, an example of conformal η-Einstein solitons on trans-Sasakian manifold is constructed.

AbstractThe object of the present paper is to study some properties of (LCS)n-manifolds whose metric is Yamabe soliton. We establish some characterization of (LCS)n-manifolds when the soliton becomes steady. Next we have studied some certain curvature conditions of (LCS)n-manifolds admitting Yamabe solitons. Lastly we construct a 3-dimensional (LCS)n-manifold satisfying the results.

Synthetic ion transporters have attracted tremendous attention for their therapeutic potential against various ion-transport-related diseases, including cancer. Inspired by the structure and biological activities of natural products, we synthesized a small series of squaramide and thiourea derivatives of quinine and investigated their ion transport activities. The involvement of a quinuclidine moiety for the cooperative interactions of Cl–and H+ions with the thiourea or squaramide moiety resulted in an effectual transport of these ions across membranes. The interference of ionic equilibrium by the potent Cl–ion carrier selectively induced cancer cell death by endorsing caspase-arbitrated apoptosis. In vivo assessment of the potent ionophore showed an efficient reduction in tumor growth with negligible immunotoxicity to other organs.

The present work aims to explore the mechanism of action of C -cinnamoyl glycoside as an antifilarial agent against the bovine filarial nematode Setaria cervi. Both apoptosis and autophagy programmed cell death pathways play a significant role in parasitic death. The generation of reactive oxygen species, alteration of the level of antioxidant components and disruption of mitochondrial membrane potential may be the causative factors that drive the parasitic death. Monitoring of autophagic flux via the formation of autophagosome and autophagolysosome was detected via CYTO ID dye. The expression profiling of both apoptotic and autophagic marker proteins strongly support the initial findings of these two cell death processes. The increased interaction of pro-autophagic protein Beclin1 with BCL-2 may promote apoptotic pathway by suppressing anti-apoptotic protein BCL-2 from its function. This in turn partially restrains the autophagic pathway by engaging Beclin1 in the complex. But overall positive increment in autophagic flux was observed. Dynamic interaction and regulative balance of these two critical cellular pathways play a decisive role in controlling disease pathogenesis. Therefore, the present experimental work may prosper the chance for C- cinnamoyl glycosides to become a potential antifilarial therapeutic in the upcoming day after detail in vivo study and proper clinical trial. [ABSTRACT FROM AUTHOR]

AbstractDetermining whether a point is contained in a polyhedron or not has been revisited many times in history as it is one of the fundamental problems in computational geometry with immense application in three dimensional CAD/CAM problems, in GIS(Geographic Information System).We at first review what has been done before and introduce theorems based on geometric concepts.

AbstractIt is well-known that Einstein manifolds play an important role in geometry as well as in general relativity. Einstein manifolds form a natural subclass of the class of quasi-Einstein manifolds. The object of the present paper is to study some geometric properties of mixed-generalized quasi-Einstein Manifolds (MG(QE)n) which admitting certain vector fields. We show the existence of MG(QE)n, by constructing several non-trivial examples. Finally we study warped product on MG(QE)nand show that M= I×M∗(dimI= 1 and dimM∗= n− 1) is a MG(QE)nif M∗is a generalized quasi-Einstein Manifold (G(QE)n).

In this paper we study characterizations of odd and even dimensional pseudo generalized quasi Einstein manifold and we give three and four dimensional examples (both Riemannian and Lorentzian) of pseudo generalized quasi Einstein manifold to show the existence of such manifold. Also in the last section we give the examples of warped product on pseudo generalized quasi Einstein manifold.

In this paper, we study the biwarped product submanifold in locally nearly metallic Riemannian manifold. We construct a non trivial example of a biwarped product submanifold in metallic Riemannian manifold. Moreover, we discuss a necessary and sufficient condition for such submanifolds to be locally trivial. Finally, we set up an inequality in locally nearly metallic Riemannian manifold for the second fundamental form with respect to some conditions. We also investigate the equality case.

Quasi-Einstein manifold and generalized quasi-Einstein manifold are the generalizations of Einstein manifold. The purpose of this paper is to study the mixed super quasi-Einstein manifold which is also the generalizations of Einstein manifold satisfying some curvature conditions. We define both Riemannian and Lorentzian doubly warped product on this manifold. Finally, we study the completeness properties of doubly warped products on MS(QE)4for both the Riemannian and Lorentzian cases.

AbstractThe object of the present paper is to study the pseudo-projective φ-recurrent and generalized projective recurrent Lorentzian α-Sasakian manifolds. Here we show that pseudo-projective φ-recurrent Lorentzian α-Sasakian Manifold is an Einstein manifold and in the case of generalized projective φ- recurrent Lorentzian α-Sasakian manifold, we find a relation between the associated 1-forms A and B. We have also proved that the characteristic vector field ξ and vector field ρassociated to the 1-forms A and B are co-directional. We also study quasi-projectively flat Lorentzian α-Sasakian manifolds.

AbstractIn this paper we have introduced the notion of almost conformai gradient shrinking Ricci soliton and established some curvature identities for almost conformai gradient shrinking Ricci soliton.

The volume of a tetrahedron is represented in terms of the twelve face angles, inradii of the faces of tetrahedron, circumradii of the faces and the radius of the sphere circumscribing the tetrahedron

AbstractIn this paper we investigate the expressions of the Ricci tensors and scalar curvatures of warped product manifold with respect to the bases and fibres when warped product manifold is a mixed super quasi-Einstein manifold. In some cases we give some obstructions to the existence of such manifolds and in the last section we give an example of warped product on mixed super quasi-Einstein manifold.

Annona reticulataLinn, has been shown to possess antipyretic, antihelmintic, hypoglycemic, antiulcer and wound healing properties. However, its immunomodulatory role is yet to be explored.

Recently, the role of cadmium (Cd) in immunosupression has gained importance. Nevertheless, the signaling pathways underlying cadmium-induced immune cell death remains largely unclear. In accordance to our previous in vivo report, and to evaluate the further details of the mechanism, we have investigated the effects of cadmium (CdCl2, H2O) on cell cycle regulation and apoptosis in splenocytes in vitro. Our results have revealed that reactive oxygen species (ROS) and p21 are involved in cell cycle arrest in a p53 independent manner but late hour apoptotic response was accompanied by the p53 up-regulation, loss of mitochondrial transmembrane potential (MTP), down-regulation of Bcl-xl, activation of caspase-3 and release of cytochrome c (Cyt c). However, pifithrin alfa (PFT-α), an inhibitor of p53, fails to rescue the cells from the cadmium-induced cell cycle arrest but prevents Bcl-xl down-regulation and loss of Δψm, which indicates that there is an involvement of p53 in apoptosis. In contrast, treatment with N-acetyl cysteine (NAC) can prevent cell cycle arrest and p21 up-regulation at early hours. Although it is clear that, NAC has no effect on apoptosis, p53 expression and MPT changes at late stage events. Taken together, we have demonstrated that cadmium promotes ROS generation, which potently initiates the cell cycle arrest at early hours and finally induces p53-dependent apoptosis at later part of the event.

Reaction of the 2-(arylazo)anilines Ar-N=N-C6H4NH2 [HLnNH2; Ar = C6H5 (HL1), p-CH3C6H4 (HL2), p-ClC6H4 (HL3)] with K2PtCl4 in dmso affords the new PtII azoimine complexes [(HLnNH)Pt(dmso)Cl] where the chloride and dmso ligands are mutually cis. In contrast, treatment of Na2PdCl4 with HLnNH2 in dmso gives the chloro-bridged palladium dimer [{(HLnNH)PdCl}2] as the major product along with [(HLnNH)2Pd] as the minor product. Further, the reaction of HLnNHCH2Ph with K2PtCl4 in dmso also gives [(HLnNH)Pt(dmso)Cl] whereas Na2PdCl4 affords the orthopalladated complexes [(LnNHCH2Ph)PdCl]. This means that the N–C(CH2Ph) bond is selectively cleaved by K2PtCl4. The reaction of [(HLnNH)Pt(dmso)Cl] with acetylacetone (acacH) gives the heteroleptic complex [(HLnNH)Pt(acac)]. [(HLnNH)Pt(dmso)Cl] and [(HLnNH)Pt(acac)] display a reversible reductive response at –1.20 and –1.46 V vs. SCE, respectively, in their cyclic voltammograms. The nature of the redox orbitals has been determined semi-empirically employing the EHMO method. The cytotoxicity of [(HL1NH)Pt(dmso)Cl] has been examined with HeLa cells and the sub-lethal dose (8 μM) determined by dose-dependence studies. The relative degree of apoptotic and necrotic cell death using a sub-lethal dose were measured by flow cytometry.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Earlier studies have demonstrated an over-expression of 9-O-acetylated sialoglycoconjugates (9-OAcSGs) on lymphoblasts, concomitant with high titers of anti-9-OAcSGs in childhood acute lymphoblastic leukemia (ALL). The present study was aimed to evaluate whether this high induction of anti-9-OAcSGs at disease presentation contributes toward immune surveillance. Accordingly, anti-9-OAcSGs were affinity purified from sera of ALL patients and normal individuals, and their specificity toward the glycotope having terminal 9-O-acetylated sialic acid-linked subterminal N-acetyl galactosamine (GalNAc) in α2–6 manner (9-OAcSAα2–6GalNAc) was established by hemagglutination assay, flow cytometry and confocal microscopy. Subclass distribution of anti-9-OAcSGs revealed a predominance of IgG2 in ALL. Analysis of glycosylation of anti-9-OAcSGs purified from sera of ALL patients (IgGALL) and normal individuals (IgGN) by digoxigenin glycan enzyme assay, fluorimetric estimation, gas–liquid chromatography and lectin-binding assays demonstrated that disease-specific antibodies differ in content and nature as compared with normal controls. Enhanced amount of 9-OAcSA-specific IgG2 induced in ALL was unable to trigger activation of FcγR, the complement cascade and cell-mediated cytotoxicity, although its glycotope-binding ability remains unaffected. Interestingly, only IgG1N emerged as the potent mediator of cell-mediated cytotoxicity, complement fixation and activator of effector cells through FcγR. In ALL, the observed subclass switching of anti-9-OAcSGs to IgG2, alteration in their glycosylation profile along with impairment of a few Fc-glycosylation-sensitive effector functions hints toward a disbalanced homeostasis, thereby evading the host defense. These findings justify further evaluation of the mechanism for functional unresponsiveness of antibodies and production of 9-OAcSA-specific chimeric antibodies with normal Fc domain for therapeutic applications.

TRAP (thrombospondin-related anonymous protein) is a sporozoite surface protein that plays a central role in hepatocyte invasion. We have developed procedures for recombinant production of the entire ECD (extracellular domain) and A domain of TRAP using bacterial- and baculovirus-expression systems respectively. The ECD and A domain were purified to homogeneity and migrated on gel-filtration columns as non-aggregated, monomeric proteins. These adhesive modules bound to HepG2 cells in a dose-dependent and bivalent cation-independent manner. The binding of ECD and the A domain to HepG2 cells was inhibited poorly by an excess of sulphatide analogues, suggesting the presence of as yet unidentified receptors for the A domain on hepatocytes. Using surface-plasmon-resonance-based sensor technology (Biacore), we demonstrate that TRAP ECD has higher affinity for heparin (KD=40 nM) compared with the A domain (KD=79 nM). We also present a three-dimensional structure of the A domain based on the crystal structure of the homologous von Willebrand factor A1 domain. The TRAP A domain shows two spatially distinct ligand-binding surfaces. One surface on the A domain contains the MIDAS (metal-ion-dependent adhesion site) motif, where point mutations of Thr131 and Asp162 correlate with impairment of cell infectivity by sporozoites. The other surface contains a putative heparin-binding site and consists of a basic residue cluster. Our studies suggest that TRAP interacts with multiple receptors during the hepatocyte invasion process. Our results also pave the way for inclusion of these high-quality recombinant TRAP domains in subunit-based vaccines against malaria.

Next to water, tea is the most ancient and widely consumed beverage in the world. Epidemiological studies have suggested a cancer protective effect, but the results obtained so far are not conclusive. In the current study, mechanisms of the apoptogenic effect of black tea extract were delineated. Black tea administration to Ehrlich’s ascites carcinoma (EAC)-bearing Swiss albino mice caused a significant decrease in the tumor cell count in a dose-dependent manner. Flowcytometric analysis showed an increase in the number of cells in the sub-G0/G1 population signifying tumor cell apoptosis by black tea. These results were further confirmed by nuclear staining that demonstrated distinct morphological features of apoptosis. Our data also revealed an increase in the expression of pro-apoptotic protein p53 in EAC. It is known that upon p53 induction, multiple downstream factors contribute to the decision making between growth arrest and apoptosis. Among those, pro-apoptotic gene Bax is up regulated during p53-mediated apoptosis. On the other hand, p53-mediated growth arrest involves p21 as a major effecter. In our system, increase in p53 expression was followed by moderate expression of p21/Waf-1 and high expression of Bax at protein levels. Interestingly, anti-apoptotic protein Bcl-2 was down regulated resulting in decrease in Bcl-2/Bax ratio. All these observations together signify that black tea-induced apoptogenic signals overrode the growth-arresting message of p21, thereby leading the tumor cells towards death.