Epitope analysis of the malaria surface antigen pfs48/45 identifies a subdomain that elicits transmission blocking antibodies

Pfs48/45, a member of a Plasmodium-specific protein family, displays conformation-dependent epitopes and is an important target for malaria transmission-blocking (TB) immunity. To design a recombinant Pfs48/45-based TB vaccine, we analyzed the conformational TB epitopes of Pfs48/45. The Pfs48/45 protein was found to consist of a C-terminal six-cysteine module recognized by anti-epitope I antibodies, a middle four-cysteine module recognized by anti-epitopes IIb and III, and an N-terminal module recognized by anti-epitope V antibodies. Refolding assays identified that a fragment of 10 cysteines (10C), comprising the middle four-cysteine and the C-terminal six-cysteine modules, possesses superior refolding capacity. The refolded and partially purified 10C conformer elicited antibodies in mice that targeted at least two of the TB epitopes (I and III). The induced antibodies could block the fertilization of Plasmodium falciparum gametes in vivo in a concentration-dependent manner. Our results provide important insight into the structural organization of the Pfs48/45 protein and experimental support for a Pfs48/45-based subunit vaccine.     

Chemogenomics and orthology‐based design of antibiotic combination therapies

Combination antibiotic therapies are being increasingly used in the clinic to enhance potency and counter drug resistance. However, the large search space of candidate drugs and dosage regimes makes the identification of effective combinations highly challenging. Here, we present a computational approach called INDIGO, which uses chemogenomics data to predict antibiotic combinations that interact synergistically or antagonistically in inhibiting bacterial growth. INDIGO quantifies the influence of individual chemical–genetic interactions on synergy and antagonism and significantly outperforms existing approaches based on experimental evaluation of novel predictions in Escherichia coli. Our analysis revealed a core set of genes and pathways (e.g. central metabolism) that are predictive of antibiotic interactions. By identifying the interactions that are associated with orthologous genes, we successfully estimated drug‐interaction outcomes in the bacterial pathogens Mycobacterium tuberculosis and Staphylococcus aureus, using the E. coli INDIGO model. INDIGO thus enables the discovery of effective combination therapies in less‐studied pathogens by leveraging chemogenomics data in model organisms.     

Structure and plasticity of Endophilin and Sorting Nexin 9

Endophilin and Sorting Nexin 9 (Snx9) play key roles in endocytosis by membrane curvature sensing and remodeling via their Bin/Amphiphysin/Rvs (BAR) domains. BAR and the related F-BAR domains form dimeric, crescent-shaped units that occur N- or C-terminally to other lipid-binding, adaptor, or catalytic modules. In crystal structures, the PX-BAR unit of Snx9 (Snx9(PX-BAR)) adopts an overall compact, moderately curved conformation. SAXS-based solution studies revealed an alternative, more curved state of Snx9(PX-BAR) in which the PX domains are flexibly connected to the BAR domains, providing a model for how Snx9 exhibits lipid-dependent curvature preferences. In contrast, Endophilin appears to be rigid in solution, and the SH3 domains are located at the distal tips of a BAR domain dimer with fixed curvature. We also observed tip-to-tip interactions between the BAR domains in a trigonal crystal form of Snx9(PX-BAR) reminiscent of functionally important interactions described for F-BAR domains.     

Carboxymethylcellulose–gelatin–superoxidase dismutase electrode for amperometric superoxide radical sensing

A novel, highly sensitive superoxide dismutase biosensor for the direct and simultaneous determination of superoxide radicals was developed by immobilization of superoxide dismutase within carboxymethylcellulose-gelatin on a Pt electrode surface. The parameters affecting the performance of the biosensor were investigated. The response of the CMC-G-SOD biosensor was proportional to O (2) (·-) concentration and the detection limit was 1.25 × 10(-3) mM with a correlation coefficient of 0.9994. The developed biosensor exhibited high analytical performance with wider linear range, high sensitivity and low response time. The biosensor retained 89.8% of its sensitivity after use for 80 days. The support system enhanced the immobilization of superoxide dismutase and promoted the electron transfer of superoxide dismutase minimizing its fouling effect. The biosensor was quite effective not only in detecting O (2) (·-) , but also in determining the antioxidant properties of acetylsalicylic acid-based drugs and the anti-radical activity of healthy and cancerous human brain tissues.     

Synthesis,cytotoxicity and carbonic anhydrase inhibitory activities of new pyrazolines

Abstract

A series of polymethoxylated-pyrazoline benzene sulfonamides were synthesized, investigated for their cytotoxic activities on tumor and non-tumor cell lines and inhibitory effects on carbonic anhydrase isoenzymes (hCA I and hCA II). Although tumor selectivity (TS) of the compounds were less than the reference compounds 5-Fluorouracil and Melphalan, trimethoxy derivatives 4, 5, and 6 were more selective than dimethoxy derivatives 2 and 3 as judged by the cytotoxicity assay with the cells both types originated from the gingival tissue. The compound 6 (4-[3-(4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl] benzene sulfonamide) showed the highest TS values and can be considered as a lead molecule of the series for further investigations. All compounds synthesized showed superior CA inhibitory activity than the reference compound acetazolamide on hCA I, and II isoenzymes, with inhibition constants in the range of 26.5–55.5?nM against hCA I and of 18.9–28.8?nM against hCA II, respectively.     

Effect of cycline D1 (CCND1) gene polymorphism on tumor formation and behavior in patients with prolactinoma

The objective of this study was to investigate the effect of G870A gene polymorphism of CCND1 on the formation and behavioral features of prolactinomas. One hundred and thirteen patients with prolactinoma and 108 age and gender matched control were included in the study. The patients were divided into two groups as noninvasive and invasive tumors. CCND1 G870A gene polymorphism was compared in patients/control and invasive/noninvasive groups. A and G allele frequencies were found as 41.7% and 58.3% in the controls, and 61.1% and 38.9% in the patients (p<0.01). Rates of G/G, G/A and A/A genotypes were found as 11.8%, 55.9% and 32.4% in the noninvasive group, and 15.6%, 44.4% and 40.0% in the invasive group, respectively. Differences between patient and control groups were significant but were not between invasive and noninvasive groups in terms of the allele frequencies and genotype distribution. Mean tumor size and serum levels of prolactin at the time of diagnosis and change in these values after the treatment were not found statistically significant in genotype subgroups. CCND1 G870A gene polymorphism may be an important factor in the early stages of the tumor formation. However, it did not affect the features of the tumor.     

Comparison of Protective Effect of Aqueous and Ethanolic Extracts of Propolis against Gastric Ulceration in Rats

This study focused on the protective effects of different types of propolis extracts on gastric mucosa in indomethacin-induced rats. The animals were divided into nine groups: control, negative control (ulcer), positive control (omeprazole), and experimental groups, which were summarized by 200, 400, and 600 mg/kg, bw for aqueous-based and ethanol, respectively. According to the histopathological evaluation, more than others, the doses of 200 and 400 mg/kg of aqueous-based propolis extracts had different degrees of positive effects on the gastric mucosa. Generally, the biochemical analyses of the gastric tissue showed a correlation with microscopic evaluations. According to the phenolic profile analysis, while pinocembrin (684.34±1.70 μg/ml) and chrysin (540.54±9.06 μg/ml) were the most abundant phenolics in the ethanolic extract, ferulic acid (53.77±0.07 μg/ml) and p-coumaric acid (52.61±0.42 μg/ml) dominated the aqueous-based extract. Also, the total phenolic content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity of the ethanolic extract showed almost nine-fold superiority compared to the aqueous-based extracts. Based on data from preclinical data, it was decided that the best doses for the main goal of the study were 200 mg and 400 mg/kg, bw for aqueous-based propolis extract.     

Germline genome editing: Moratorium,hard law,or an informed adaptive consensus?

With the development of practical means of human germline genome editing (HGGE) in recent years, there have been calls for stricter regulation and oversight over HGGE interventions with potential for heritable changes in the germline. An international moratorium has been advocated. We examine the practicality of such a proposal, as well as of a regulation through the “traditional” mechanisms of international and municipal laws. We argue that these mechanisms are unlikely to achieve their intended objectives and that the better approach is to engage the international community of stakeholders, researchers, scientists, clinicians, and other workers directly involved in the field in working toward the development of an “informed adaptive consensus”. We offer suggestions as to how this may be achieved and how existing indirect levers of regulation may be harnessed toward this end.