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Current strategies for the delivery of proteins into cells face general challenges of endosomal entrapment and concomitant degradation of protein cargo. Efficient delivery directly to the cytosol overcomes this obstacle: we report here the use of biotin-streptavidin tethering to provide a modular approach to the generation of nanovectors capable of a cytosolic delivery of biotinylated proteins. This strategy uses streptavidin to organize biotinylated protein and biotinylated oligo(glutamate) peptide into modular complexes that are then electrostatically self-assembled with a cationic guanidinium-functionalized polymer. The resulting polymer-protein nanocomposites demonstrate efficient cytosolic delivery of six biotinylated protein cargos of varying size, charge, and quaternary structure. Retention of protein function was established through efficient cell killing via delivery of the chemotherapeutic enzyme granzyme A. This platform represents a versatile and modular approach to intracellular delivery through the noncovalent tethering of multiple components into a single delivery vector.

Control over supramolecular recognition between proteins and nanoparticles (NPs) is of fundamental importance in therapeutic applications and sensor development. Most NP-protein binding approaches use 'tags' such as biotin or His-tags to provide high affinity; protein surface recognition provides a versatile alternative strategy. Generating high affinity NP-protein interactions is challenging however, due to dielectric screening at physiological ionic strengths. We report here the co-engineering of nanoparticles and protein to provide high affinity binding. In this strategy, 'supercharged' proteins provide enhanced interfacial electrostatic interactions with complementarily charged nanoparticles, generating high affinity complexes. Significantly, the co-engineered protein-nanoparticle assemblies feature high binding affinity even at physiologically relevant ionic strength conditions. Computational studies identify both hydrophobic and electrostatic interactions as drivers for these high affinity NP-protein complexes.

Human cyclophilin B (CypB) is oversecreted by pancreatic cancer cells, making it a potential biomarker for early-stage disease diagnosis. Our group is motivated to develop aptamer-based assays to measure CypB levels in biofluids. However, human cyclophilins have been postulated to have collateral nuclease activity, which could impede the use of aptamers for CypB detection. To establish if CypB can hydrolyze electrode-bound nucleic acids, we used ultrasensitive electrochemical sensors to measure CypB's hydrolytic activity. Our sensors use ssDNA and dsDNA in the biologically predominant d-DNA form, and in the nuclease resistant l-DNA form. Challenging such sensors with CypB and control proteins, we unequivocally demonstrate that CypB can cleave nucleic acids. To our knowledge, this is the first study to use electrochemical biosensors to reveal the hydrolytic activity of a protein that is not known to be a nuclease. Future development of CypB bioassays will require the use of nuclease-resistant aptamer sequences.

Nanocarrier-mediated protein delivery is a promising strategy for fundamental research and therapeutic applications. However, the efficacy of the current platforms for delivery into cells is limited by endosomal entrapment of delivered protein cargo with concomitantly inefficient access to the cytosol and other organelles, including the nucleus. We report here a robust, versatile polymeric-protein nanocomposite (PPNC) platform capable of efficient (≥90%) delivery of proteins to the cytosol. We synthesized a library of guanidinium-functionalized poly(oxanorborneneimide) (PONI) homopolymers with varying molecular weights to stabilize and deliver engineered proteins featuring terminal oligoglutamate "E-tags". The polymers were screened for cytosolic delivery efficiency using imaging flow cytometry with cytosolic delivery validated using confocal microscopy and activity of the delivered proteins demonstrated through functional assays. These studies indicate that the PPNC platform provides highly effective and tunable cytosolic delivery over a wide range of formulations, making them robust agents for therapeutic protein delivery.

The development of marital health as a bona fide health field is posited as the most viable means for obtaining funding for training, research and treatment concerning the marital dyad equal to such funding now available for other health fields. (Author)

Initial research report of project on knowledge, attitudes, and practices of family planning. Uses data from 1960 census, updated to 1964, for area of high proportion of poverty-level blacks to support general hypothesis that illegitimacy "runs in families among both poverty-level and lower-middle income black females. (Author/CJ)

Using the 100% relative‐humidity technique for controlling the mole function of water vapor, the Napier (relaxation) frequency of oxygen has been measured as a function of the mole fraction of various water vapors, consisting of pure H2O, pure D2O, and three mixtures thereof. Pure H2O gives, as is well known, a quadratic in H, the mole fraction; pure D2O gives a linear relation down to 0.7×10−3. The mixtures show a linear relation above 1.5×10−3 and a curvilinear approach to zero below that. Calculation indicates that the heterogeneous molecule HDO is far more effective as a thermal equilibrator for oxygen than either of its homogeneous parents. Quantitatively, with (f/p)m in cps per atm and h in mole fraction ×103, the results are:100% H2O: (f/p)m = 7+183h+132h2;50% D2O: (f/p)m = −664+1100h;80% D2O: (f/p)m = −490+908h;92% D2O: (f/p)m = −250+585h(above h = 1.3);92% D2O: (f/p)m = 7+275h+100h2(below h = 1.3);99.8% D2O: (f/p)m = −85+385h.

The great amount of attention now being given to the question of poor power factor suggests that tariffs such as are commonly used to-day are unsuitable in present circumstances. The paper contends that a wattless component of current, despite its having no energy content, involves the supply undertaking in extra running costs, and that therefore a charge should be levied for supplying it. A three-part tariff is proposed, embracing a periodic charge per kVA of maximum demand, a charge per kWh of energy, and a charge per kVA-hour of lagging wattless component. The additional running costs caused by wattless component are briefly touched on, and it is suggested that in a station with an average power factor of 0.7 the charge per kVA-hour of wattless component should be about one-ninth of the charge per kWh of energy. The question of metering the three-part tariff is discussed, and a method is shown whereby, with balanced load, a three-phase wattmeter may be ?biased? to record the total energy consumption, plus or minus any desired fraction of the kVA-hours of lagging or leading wattless component.