Exploiting the antivirulence efficacy of an ajoene-ciprofloxacin combination against Pseudomonas aeruginosa biofilm associated murine acute pyelonephritis

The study investigated the in vitro, ex vivo and in vivo efficacy of ajoene and ciprofloxacin (CIP) alone and in combination against Pseudomonas aeruginosa biofilms and biofilm-associated murine acute pyelonephritis. The ajoene–CIP combination exhibited significant greater (p < 0.05) antimotility and biofilm inhibitory effects than those obtained when they were applied individually. The combined action of the agents resulted in a significant increase in serum sensitivity and phagocytic uptake and killing of P. aeruginosa (p < 0.001) compared to the untreated control. Mice groups treated with an ajoene (25 mg kg^?1) and CIP (30 mg kg^?1 or 15 mg kg^?1) combination showed a significantly (p < 0.001) reduced bacterial load in the kidney and bladder as compared to that of infected controls and mice treated with solo agents on the fifth day post-infection. The decreased levels of biomarkers and photomicrographs of the kidney tissue of the treated mice showed a reduced severity of damage. Hence, the study highlights the antivirulent and therapeutic efficacy of the ajoene-CIP combination at the minimal dosage of CIP.     

Aromatic-aromatic interactions: analysis of π-π interactions in interleukins and TNF proteins

Aromatic-aromatic hydrogen bonds are important in many areas of chemistry, biology and materials science. In this study we have analyzed the roles played by the π-π interactions in interleukins (ILs) and tumor necrosis factor (TNF) proteins. Majority of π-π interacting residues are conserved in ILs and TNF proteins. The accessible surface area calculations in these proteins reveal that these interactions might be important in stabilizing the inner core regions of these proteins. In addition to π-π interactions, the aromatic residues also form π-networks in ILs and TNF proteins. The results obtained in the present study indicate that π-π interactions and π-π networks play important roles in the structural stability of ILs and TNF proteins.     

Development of fluorescence imaging probes for nicotinic acetylcholine α4β21 receptors

Nicotinic acetylcholine α4β2¹ receptors (nAChRs) are implicated in various neurodegenerative diseases and smoking addiction. Imaging of brain high-affinity α4β2¹ nAChRs at the cellular and subcellular levels would greatly enhance our understanding of their functional role. Since better resolution could be achieved with fluorescent probes, using our previously developed positron emission tomography (PET) imaging agent [¹⁸F]nifrolidine, we report here design, synthesis and evaluation of two fluorescent probes, nifrodansyl and nifrofam for imaging α4β2¹ nAChRs. The nifrodansyl and nifrofam exhibited nanomolar affinities for the α4β2¹ nAChRs in [³H]cytisine-radiolabeled rat brain slices. Nifrofam labeling was observed in α4β2¹ nAChR-expressing HEK cells and was upregulated by nicotine exposure. Nifrofam co-labeled cell-surface α4β2¹ nAChRs, labeled with antibodies specific for a β2 subunit extracellular epitope indicating that nifrofam labels α4β2¹ nAChR high-affinity binding sites. Mouse brain slices exhibited discrete binding of nifrofam in the auditory cortex showing promise for examining cellular distribution of α4β2¹ nAChRs in brain regions.     

Nevirapine Resistance and Breast-Milk HIV Transmission: Effects of Single and Extended-Dose Nevirapine Prophylaxis in Subtype C HIV-Infected Infants

Background

Daily nevirapine (NVP) prophylaxis to HIV-exposed infants significantly reduces breast-milk HIV transmission. We assessed NVP-resistance in Indian infants enrolled in the “six-week extended-dose nevirapine” (SWEN) trial who received single-dose NVP (SD-NVP) or SWEN for prevention of breast-milk HIV transmission but who also acquired subtype C HIV infection during the first year of life.

Methods/Findings

Standard population sequencing and cloning for viral subpopulations present at ≥5% frequency were used to determine HIV genotypes from 94% of the 79 infected Indian infants studied. Timing of infection was defined based on when an infant''s blood sample first tested positive for HIV DNA. SWEN-exposed infants diagnosed with HIV by six weeks of age had a significantly higher prevalence of NVP-resistance than those who received SD-NVP, by both standard population sequencing (92% of 12 vs. 38% of 29; p = 0.002) and low frequency clonal analysis (92% of 12 vs. 59% of 29; p = 0.06). Likelihood of infection with NVP-resistant HIV through breast-milk among infants infected after age six weeks was substantial, but prevalence of NVP-resistance did not differ among SWEN or SD-NVP exposed infants by standard population sequencing (15% of 13 vs. 15% of 20; p = 1.00) and clonal analysis (31% of 13 vs. 40% of 20; p = 0.72). Types of NVP-resistance mutations and patterns of persistence at one year of age were similar between the two groups. NVP-resistance mutations did differ by timing of HIV infection; the Y181C variant was predominant among infants diagnosed in the first six weeks of life, compared to Y188C/H during late breast-milk transmission.

Conclusions/Significance

Use of SWEN to prevent breast-milk HIV transmission carries a high likelihood of resistance if infection occurs in the first six weeks of life. Moreover, there was a continued risk of transmission of NVP-resistant HIV through breastfeeding during the first year of life, but did not differ between SD-NVP and SWEN groups. As with SD-NVP, the value of preventing HIV infection in a large number of infants should be considered alongside the high risk of resistance associated with extended NVP prophylaxis.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00061321","term_id":"NCT00061321"}}NCT00061321     

Combinatorial anticancer effects of curcumin and 5-fluorouracil loaded thiolated chitosan nanoparticles towards colon cancer treatment

Background

Evaluation of the combinatorial anticancer effects of curcumin/5-fluorouracil loaded thiolated chitosan nanoparticles (CRC-TCS-NPs/5-FU-TCS-NPs) on colon cancer cells and the analysis of pharmacokinetics and biodistribution of CRC-TCS-NPs/5-FU-TCS-NPs in a mouse model.

Methods

CRC-TCS-NPs/5-FU-TCS-NPs were developed by ionic cross-linking. The in vitro combinatorial anticancer effect of the nanomedicine was proven by different assays. Further the pharmacokinetics and biodistribution analyses were performed in Swiss Albino mouse using HPLC.

Results

The 5-FU-TCS-NPs (size: 150 ± 40 nm, zeta potential: + 48.2 ± 5 mV) and CRC-TCS-NPs (size: 150 ± 20 nm, zeta potential: + 35.7 ± 3 mV) were proven to be compatible with blood. The in vitro drug release studies at pH 4.5 and 7.4 showed a sustained release profile over a period of 4 days, where both the systems exhibited a higher release in acidic pH. The in vitro combinatorial anticancer effects in colon cancer (HT29) cells using MTT, live/dead, mitochondrial membrane potential and cell cycle analysis measurements confirmed the enhanced anticancer effects (2.5 to 3 fold). The pharmacokinetic studies confirmed the improved plasma concentrations of 5-FU and CRC up to 72 h, unlike bare CRC and 5-FU.

Conclusions

To conclude, the combination of 5-FU-TCS-NPs and CRC-TCS-NPs showed enhanced anticancer effects on colon cancer cells in vitro and improved the bioavailability of the drugs in vivo.

General significance

The enhanced anticancer effects of combinatorial nanomedicine are advantageous in terms of reduction in the dosage of 5-FU, thereby improving the chemotherapeutic efficacy and patient compliance of colorectal cancer cases.     

Mass-Spectrometric Identification of T-Kininogen I/Thiostatin as an Acute-Phase Inflammatory Protein Suppressed by Curcumin and Capsaicin

Curcumin and capsaicin are dietary xenobiotics with well-documented anti-inflammatory properties. Previously, the beneficial effect of these spice principles in lowering chronic inflammation was demonstrated using a rat experimental model for arthritis. The extent of lowering of arthritic index by the spice principles was associated with a significant shift in macrophage function favoring the reduction of pro-inflammatory molecules such as reactive oxygen species and production and release of anti-inflammatory metabolites of arachidonic acid. Beyond the cellular effects on macrophage function, oral administration of curcumin and capsaicin caused alterations in serum protein profiles of rats injected with adjuvant to develop arthritis. Specifically, a 72 kDa acidic glycoprotein, GpA72, which was elevated in pre-arthritic rats, was significantly lowered by feeding either curcumin or capsaicin to the rats. Employing the tandem mass spectrometric approach for direct sequencing of peptides, here we report the identification of GpA72 as T-kininogen I also known as Thiostatin. Since T-kininogen I is an early acute-phase protein, we additionally tested the efficiency of curcumin and capsaicin to mediate the inflammatory response in an acute phase model. The results demonstrate that curcumin and capsaicin lower the acute-phase inflammatory response, the molecular mechanism for which is, in part, mediated by pathways associated with the lowering of T-kininogen I.     

In Silico Analysis of Natural Resistance-Associated Macrophage Protein (NRAMP) Family of Transporters in Rice

In Oryza sativa (rice) there are seven members in the NRAMP (natural resistance- associated macrophage protein) family of transporter proteins. They have been identified as OsNRAMP1, OsNRAMP2, OsNRAMP3, OsNRAMP4, OsNRAMP5, OsNRAMP6 and OsNRAMP7. Several metal ions like Zn²⁺, Mn²⁺, Fe²⁺, Cd²⁺ etc. have been studied to be transported via NRAMP transporter proteins in rice plant. In spite of this, very little information is available regarding these transporters. Hence it is important to computationally predict and characterize the OsNRAMP family of transporters for studying and understanding their molecular insights in future studies. For this purpose, various in silico methods and tools were used for the characterization of OsNRAMP family of transporter proteins. Physico-chemical properties of the protein sequences were calculated, putative transmembrane domains (TMDs) and conserved motif signatures were determined and their interaction partners were predicted. 3D models of all the members of OsNRAMP transporters were generated using online structure prediction tool followed by their analysis. In silico microarray analysis was done to understand the expression pattern of these transporters in rice plant. Currently, only limited knowledge is available about the structural and functional aspects of these transporters, hence this study would provide more theoretical information about them.     

Associations of Maternal Diabetes During Pregnancy with Overweight in Offspring: Results from the Prospective TEDDY Study

Objective: This study aimed to determine the relationship between different forms of, and potential pathways between, maternal diabetes and childhood obesity at different ages. Methods: Prospective cohort data from The Environmental Determinants of Diabetes in the Young (TEDDY) study, which was composed of 5,324 children examined from 0.25 to 6 years of age, were analyzed. Cross‐sectional and longitudinal analyses taking into account potential confounders and effect modifiers such as maternal prepregnancy BMI and birth weight z scores were performed. Results: Offspring of mothers with gestational diabetes mellitus (GDM) or type 1 diabetes mellitus (T1DM) showed a higher BMI standard deviation score and increased risk for overweight and obesity at 5.5 years of age than offspring of mothers without diabetes. While these associations could be substantially explained by maternal prepregnancy BMI in offspring of mothers with GDM, significant associations disappeared after adjustment for birth weight z scores in offspring of T1DM mothers. Furthermore, overweight risk became stronger with increasing age in offspring of mothers with diabetes compared with offspring of mothers without diabetes. Conclusions: Maternal diabetes is associated with increased risk of offspring overweight, and the association appears to get stronger as children grow older. Indeed, intrauterine exposure to maternal T1DM may predispose children to later obesity through increased birth weight, while maternal BMI is more important in children exposed to GDM.     

Agronomic improvements can make future cereal systems in South Asia far more productive and result in a lower environmental footprint

South Asian countries will have to double their food production by 2050 while using resources more efficiently and minimizing environmental problems. Transformative management approaches and technology solutions will be required in the major grain‐producing areas that provide the basis for future food and nutrition security. This study was conducted in four locations representing major food production systems of densely populated regions of South Asia. Novel production‐scale research platforms were established to assess and optimize three futuristic cropping systems and management scenarios (S2, S3, S4) in comparison with current management (S1). With best agronomic management practices (BMPs), including conservation agriculture (CA) and cropping system diversification, the productivity of rice‐ and wheat‐based cropping systems of South Asia increased substantially, whereas the global warming potential intensity (GWPi) decreased. Positive economic returns and less use of water, labor, nitrogen, and fossil fuel energy per unit food produced were achieved. In comparison with S1, S4, in which BMPs, CA and crop diversification were implemented in the most integrated manner, achieved 54% higher grain energy yield with a 104% increase in economic returns, 35% lower total water input, and a 43% lower GWPi. Conservation agriculture practices were most suitable for intensifying as well as diversifying wheat–rice rotations, but less so for rice–rice systems. This finding also highlights the need for characterizing areas suitable for CA and subsequent technology targeting. A comprehensive baseline dataset generated in this study will allow the prediction of extending benefits to a larger scale.