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Mycobacterium bovi s is an etiological agent of bovine tuberculosis (bTB) that also infects other mammals, including humans. The lack of an effective vaccine for the control of bTB highlights the need for developing new vaccines. In this study, we developed and evaluated an M. bovis strain deleted in the virulence genes phoP , esxA and esxB as a vaccine candidate against bTB in BALBc mice. The evaluated strains were the new live vaccine and BCG, alone or in combination with ncH65vD. The immunogen ncH65vD is a fusion protein H65, encapsulated together with vitamin D3, within the oily body of a nanocapsule composed of an antigen-loading polymeric shell. All vaccines conferred protection against the M. bovis challenge. However, no significant differences were detected among the vaccinated groups regarding bacterial loads in lungs and spleen. Mice vaccinated with the mutant strain plus ncH65vD showed negative Ziehl Neelsen staining of mycobacteria in their lungs, which suggests better control of bacteria replication according to this protection parameter. Consistently, this vaccination scheme showed the highest proportion of CD4 + T cells expressing the protection markers PD-1 and CXCR3 among the vaccinated groups. Correlation studies showed that PD-1 and CXCR3 expression levels in lung-resident CD4 T cells negatively correlated with the number of colony forming units of M. bovis in the lungs of mice. Therefore, the results suggest a link between the presence of PD-1 + and CXCR3 + cells at the site of the immune response against mycobacteria and the level of mycobacterial loads. • Vaccination with Mb303Δ3 plus ncH65vD protected mice against M. bovis challenge. • CD4 +CXCR3 + negatively correlated with CFU in lungs of M. bovis -infected mice. • CD4 +PD1 + negatively correlated with CFU in lungs of vaccinated and infected mice. [ABSTRACT FROM AUTHOR]

Hydrochlorothiazide (HCT) is one of the most commonlyprescribedantihypertensive drugs. In an attempt to gain an insight into thephysicochemical and molecular aspects controlling the complex architectureof native β-cyclodextrin (β-CD) with HCT, we performedmultiple-temperature–pH isothermal titration calorimetric measurementsof the HCT:β-CD system, together with proton nuclear magneticresonance spectroscopy (1H NMR), phase solubility analysis,and molecular modeling methods. The AL-type diagrams, obtainedat different pH values and temperatures, suggested the formation ofsoluble 1:1 inclusion complexes of β-CD with HCT. The correspondingstability constants (K1:1) were determinedby phase solubility studies and compared with those obtained by ITC,with good agreement between these two techniques being found. Thethree-dimensional array of the complex was studied by 1H NMR and molecular modeling methods. Both techniques confirmed theformation of the inclusion complex, with good agreement between theexperimental and theoretical techniques regarding the HCT bindingmode to β-CD. Also, the forces involved in the association processwere determined, both from the thermodynamic parameters obtained byITC (association enthalpy, binding constant, Gibbs free energy, andentropy) and from energetic decomposition analyses derived from computationalmethods. We concluded that the formation of the HCT:β-CD complexwas enthalpy driven, with the inclusion mode of HCT being highly dependenton its ionization state. In all cases, sustained hydrogen bond interactionswith hydroxyl groups of β-CD were identified, with the solvationenergy limiting the affinity. Regarding the pH and temperature dependence,lower affinity constants were found at higher HCT ionization statesand temperatures. [ABSTRACT FROM AUTHOR]

Abstract: The complex formation of chlorhexidine digluconate (CHX-G2) with hydroxypropyl-β-cyclodextrin (HPβCD) was studied using NMR spectroscopy. The results revealed that this surfactant agent shows an monomer/aggregate equilibrium, which is dependent on the concentration of this drug. This equilibrium can be modified by the presence of HPβCD, which reduces the aggregation of the CHX-G2 molecules. An inclusion process of the CHX-G2 aromatic residue within the cyclodextrin cavity was confirmed by 2D ROESY spectroscopy. 1H NMR titration studies of CHX-G2 with HPβCD in D2O confirmed the formation of higher order complexes between CHX-G2 and HPβCD. Moreover, the addition of HPβCD into CHX-G2 solutions forms insoluble aggregates. Such insoluble aggregates may result in the stacking of CHX-G2 molecules on the surface of the CHX-G2:HPβCD complexes. [Copyright &y& Elsevier]