Immune Responses to the O-Specific Polysaccharide Antigen in Children Who Received a Killed Oral Cholera Vaccine Compared to Responses following Natural Cholera Infection in Bangladesh

Current oral cholera vaccines induce lower levels of protective efficacy and shorter durations of protection in young children than in adults. Immunity against cholera is serogroup specific, and immune responses to Vibrio cholerae lipopolysaccharide (LPS), the antigen that mediates serogroup-specific responses, are associated with protection against disease. Despite this, responses against V. cholerae O-specific polysaccharide (OSP), a key component of the LPS responsible for specificity, have not been characterized in children. Here, we report a comparison of polysaccharide antibody responses in children from a region in Bangladesh where cholera is endemic, including infants (6 to 23 months, n = 15), young children (24 to 59 months, n = 14), and older children (5 to 15 years, n = 23) who received two doses of a killed oral cholera vaccine 14 days apart. We found that infants and young children receiving the vaccine did not mount an IgG, IgA, or IgM antibody response to V. cholerae OSP or LPS, whereas older children showed significant responses. In comparison to the vaccinees, young children with wild-type V. cholerae O1 Ogawa infection did mount significant antibody responses against OSP and LPS. We also demonstrated that OSP responses correlated with age in vaccinees, but not in cholera patients, reflecting the ability of even young children with wild-type cholera to develop OSP responses. These differences might contribute to the lower efficacy of protection rendered by vaccination than by wild-type disease in young children and suggest that efforts to improve lipopolysaccharide-specific responses might be critical for achieving optimal cholera vaccine efficacy in this younger age group.     

Synthesis and in vitro anti-proliferative evaluation of naphthalimide–chalcone/pyrazoline conjugates as potential SERMs with computational validation

A series of naphthalimide-chalcone/pyrazoline conjugates was prepared and evaluated for their anti-breast cancer potential against estrogen responsive, i.e. MCF-7 (ER+), and triple-negative, i.e. MDA-MB-231 (ER−), cell lines. The structure-activity-relationship (SAR) was deduced based on the influence of linker length, substituents on the phenyl ring and the generated functionalities, on anti-proliferative activities. Docking simulations further delineate the type of interactions of the designed molecules with the selected targets. This report discloses the scope of triazole tethered naphthalimide-chalcone/pyrazoline conjugates as anti breast cancer agents.

Design, synthesis and anti-proliferative evaluation of naphthalimide–chalcone/pyrazoline conjugates.     

A DFT study to probe homo-conjugated norbornylogous bridged spacers in dye-sensitized solar cells: an approach to suppressing agglomeration of dye molecules

This work reports a sigma-bridged framework as spacers to design new dye-sensitized solar cells. The norbornylogous bridged spacer can avoid π–π aggregation of dye molecules on the semiconductor surface in DSSCs. These sesquinorbornatrienes are known to exhibit electron propagation through the interaction of sigma and π orbitals via through bond (OITB) and through space (OITS) mechanisms. Density functional theory (DFT) calculations performed with these spacers and a modelled simple donor unit like N,N-dimethylamine and cyanoacrylic acid as the anchoring group showed significant results with the requisite optical parameters for DSSCs. The newly designed dyes have shown comparable or better optical properties compared to the reference dye molecule with π-conjugated thiophene spacer units. The ΔG_injection, V_OC and μ_normal values calculated for the designed dyes were found to be higher than those of the reference system. The trans-sesquinorbornatriene system spacer (6-D) showed a V_OC of 3.3 eV, ΔG_injection of 2.4 eV and oscillatory strength (f) of 0.96. The total and partial density of states indicates a good communication between the valence and conduction band for the designed dyes. Transition density matrix results suggest that the exciton dissociation in the excited state is sufficiently high to overcome the coulombic attraction of the hole. These results are promising for the design of dye molecules with such scaffolds, to achieve better efficiency and to eliminate one of the major issues with π-spacer units in DSSCs.

This work reports homoconjugated norbornylogous spacers to supress agglomeration of dye molecules with improved efficiency of dye sensitized solar cells.     

Post-mastectomy reconstruction: A risk-stratified comparative analysis of outcomes

IntroductionAlthough breast reconstruction following mastectomy plays a role in the psychological impact of breast cancer, only one in three women undergo reconstruction. Few multi-institutional studies have compared complication profiles of reconstructive patients to non-reconstructive.MethodsUsing the National Surgical Quality Improvement database, all patients undergoing mastectomy from 2006 to 2010, with or without reconstruction, were identified and risk-stratified using propensity scored quintiles. The incidence of complications and comorbidities were compared.ResultsOf 37,723 mastectomies identified, 30% received immediate breast reconstruction. After quintile matching for comorbidities, complications rates between reconstructive and non-reconstructives were similar. This trend was echoed across all quintiles, except in the sub-group with highest comorbidities. Here, the reconstructive patients had significantly more complications than the non-reconstructive (22.8% versus 7.0%, p < 0.001).ConclusionImmediate breast reconstruction is a well-tolerated surgical procedure. However, in patients with high comorbidities, surgeons must carefully counterbalance surgical risks with psychosocial benefits to maximize patient outcomes.Level of evidenceLevel 3