Physiological Compatibility Research Articles

Injectable, strong and bioadhesive catechol-chitosan hydrogels physically crosslinked using sodium bicarbonate

Fast-gelling chitosan thermosensitive hydrogels have proven to be excellent matrices for targeted drug-delivery and cell therapy. In this work, we demonstrate the possibility of designing injectable bioadhesive hydrogels with a high gelation rate by modifying chitosan with catechol (cat-CH) and using sodium bicarbonate (SHC) as a gelling agent. Cat-CH/SHC hydrogels gel under 5 min at 37 °C and reach a high secant modulus after 24 h (E = 90 kPa at 50% strain). Besides, they show significantly higher adhesion to tissues than chitosan hydrogels thanks to the combination of catechol grafting and physical crosslinking. Their pH and osmolality stayed inside the physiological range. While biocompability tests will be mandatory to conclude regarding their potential for drug or cell encapsulation, these hydrogels uniquely combine physiological compatibility, injectability, fast gelation, good cohesion, and bioadhesion.

Folic Acid-Modified Nanoerythrocyte for Codelivery of Paclitaxel and Tariquidar to Overcome Breast Cancer Multidrug Resistance.

The efflux of anticancer agents mediated by P-glycoprotein (P-gp) is one of the main causes of multidrug resistance (MDR) and eventually leads to chemotherapy failure. To overcome this problem, the delivery of anticancer agents in combination with a P-gp inhibitor using nanocarrier systems is considered an effective strategy. On the basis of the physiological compatibility and excellent drug loading ability of erythrocytes, we hypothesized that nanoerythrocytes could be used for the codelivery of an anticancer agent and a P-gp inhibitor to overcome MDR in breast cancer. Herein, a folic acid-modified nanoerythrocyte system (PTX/TQR NPs@NanoRBC-PEG/FA) was prepared to simultaneously transport paclitaxel and tariquidar, and the in vitro and in vivo characteristics of this delivery system were evaluated through several experiments. The results indicated that the average diameter and surface potential of this nanocarrier system were 159.8 ± 1.4 nm and -10.98 mV, respectively. Within 120 h, sustained release of paclitaxel was observed in both pH 6.5 media and pH 7.4 media. Tariquidar release from this nanocarrier suppressed the P-gp function of MCF-7/Taxol cells and significantly increased the intracellular paclitaxel level (p < 0.01 versus the PTX group). The results of the MTT assay indicated that the simultaneous transportation of paclitaxel and tariquidar could significantly inhibit the growth of MCF-7 cells or MCF-7/Taxol cells. After 48 h of incubation with PTX/TQR NPs@NanoRBC-PEG/FA, the viability of MCF-7 cells and MCF-7/Taxol cells decreased to 7.37% and 30.2%, respectively, and the IC50 values were 2.49 μM and 6.30 μM. Pharmacokinetic results illustrated that, compared with free paclitaxel, all test paclitaxel nanoformulations prolonged the drug release time and showed similar plasma concentration-time profiles. The peak concentration (Cmax), area under the curve (AUC0-∞), and half-life (t1/2) of PTX/TQR NPs@NanoRBC-PEG/FA were 3.33 mg/L, 6.02 mg/L·h, and 5.84 h, respectively. Moreover, this active targeting nanocarrier dramatically increased the paclitaxel level in tumor tissues. Furthermore, compared with those of the other paclitaxel formulations, the cellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels of the PTX/TQR NPs@NanoRBC-PEG/FA group increased by 1.38-fold (p < 0.01) and 1.36-fold (p < 0.01), respectively, and the activities of superoxide dismutase (SOD) and catalase (CAT) decreased to 67.8% (p < 0.01) and 65.4% (p < 0.001), respectively. More importantly, in vivo antitumor efficacy results proved that the PTX/TQR NPs@NanoRBC-PEG/FA group exerted an outstanding tumor inhibition effect with no marked body weight loss and fewer adverse effects. In conclusion, by utilizing the inherent and advantageous properties of erythrocytes and surface modification strategies, this biomimetic targeted drug delivery system provides a promising platform for the codelivery of an anticancer agent and a P-gp inhibitor to treat MDR in breast cancer.

In situ and low-cost monitoring of particles falling from freshwater animals: from microplastics to parasites.

A simple and low-cost method of monitoring and collecting particulate matter detaching from (or interacting with) aquatic animals is described using a novel device based on an airlift pump principle applied to floating cages. The efficiency of the technique in particle collection is demonstrated using polyethylene microspheres interacting with a cyprinid fish (Carassius carassius) and a temporarily parasitic stage (glochidia) of an endangered freshwater mussel (Margaritifera margaritifera) dropping from experimentally infested host fish (Salmo trutta). The technique enables the monitoring of temporal dynamics of particle detachment and their continuous collection both in the laboratory and in situ, allowing the experimental animals to be kept under natural water quality regimes and reducing the need for handling and transport. The technique can improve the representativeness of current experimental methods used in the fields of environmental parasitology, animal feeding ecology and microplastic pathway studies in aquatic environments. In particular, it makes it accessible to study the physiological compatibility of glochidia and their hosts, which is an essential but understudied autecological feature in mussel conservation programs worldwide. Field placement of the technique can also aid in outreach programs with pay-offs in the increase of scientific literacy of citizens concerning neglected issues such as the importance of fish hosts for the conservation of freshwater mussels.

METABOLISM AND MECHANISM OF TOXICITY OF SELENIUM-CONTAINING SUPPLEMENTS USED FOR OPTIMIZING HUMAN SELENIUM STATUS

The work presents a review devoted to the metabolism and the mechanism of toxicity of seleniumcontaining supplements: elemental selenium, sodium selenite, diacetophenonyl selenide, selenopyrane, ebselen, dimethyl dipyrasolyl selenide and selenium-containing amino acids used for correction of selenium deficiency. Elemental selenium penetrating through cell walls, but not through transport channels demonstrates poorly predicted and difficultly regulated bioavailability. Sodium selenate is known to be the most toxic form of selenium in food. The metabolism of xenobiotic diacetophenonyl selenide resembles that of sodium selenide. The xenobiotic reacts with thiols, for instance, with the reduced form of glutathione leading to the formation of hydrogen selenide. Ebselen is not considered to be a well bioavailable form of selenium and thus possesses low toxicity. Xenobiotic selenopyrane eliminates selenium only in processes of xenobiotic liver exchange, and in our investigations - partially in acid-catalyzed hydrolysis. The metabolism of xenobiotic dimethyl dipyrasolyl selenide having low toxicity is poorly investigated. The toxicity of high doses of selenomethionine is determined by the possibility of incorporation in proteins and vitally important enzymes with dramatic changes of protein quaternary structure. The toxicity of high doses of methylselenocysteine seems to be caused by the lack of an exchange pool in the body and quick regeneration of hydrogen selenide from methylselenol which is formed as a result of enzymatic destruction of this amino acid. Also the issue of the most prospect selenium donor is discussed. The physiological compatibility, the low toxicity, the presence of an exchangeable pool in the organism, the antioxidantal properties and the simplicity of production indicate selenocystine as an optimal selenium donor.

Окисно-відновний баланс питної води – показник її якості та фізіологічної повноцінності

Окисно-відновний баланс питної води – показник її якості та фізіологічної повноцінності

Can we predict the success of a parasite to colonise an invasive host?

To understand whether a parasite can exploit a novel invasive host species, we measured reproductive performance (number of eggs per female per day, egg size, development rate and size of new imagoes) of fleas from the Negev desert in Israel (two host generalists, Synosternus cleopatrae and Xenopsylla ramesis, and a host specialist, Parapulex chephrenis) when they exploited either a local murid host (Gerbillus andersoni, Meriones crassus and Acomys cahirinus) or two alien hosts (North American heteromyids, Chaetodipus penicillatus and Dipodomys merriami). We asked whether (1) reproductive performance of a flea differs between an alien and a characteristic hosts and (2) this difference is greater in a host specialist than in host generalists. The three fleas performed poorly on alien hosts as compared to local hosts, but the pattern of performance differed both among fleas and within fleas between alien hosts. The response to alien hosts did not depend on the degree of host specificity of a flea. We conclude that successful parasite colonisation of an invasive host is determined by some physiological, immunological and/or behavioural compatibility between a host and a parasite. This compatibility is unique for each host-parasite association, so that the success of a parasite to colonise an invasive host is unpredictable.

Infection patterns and molecular data reveal host and tissue specificity of Posthodiplostomum species in centrarchid hosts.

Posthodiplostomum minimum utilizes a three-host life cycle with multiple developmental stages. The metacercarial stage, commonly known as 'white grub', infects the visceral organs of many freshwater fishes and was historically considered a host generalist due to its limited morphological variation among a wide range of hosts. In this study, infection data and molecular techniques were used to evaluate the host and tissue specificity of Posthodiplostomum metacercariae in centrarchid fishes. Eleven centrarchid species from three genera were collected from the Illinois portion of the Ohio River drainage and necropsied. Posthodiplostomum infection levels differed significantly by host age, host genera and infection locality. Three Posthodiplostomum spp. were identified by DNA sequencing, two of which were relatively common within centrarchid hosts. Both common species were host specialists at the genus level, with one species restricted to Micropterus hosts and the other preferentially infecting Lepomis. Host specificity is likely dictated by physiological compatibility and deviations from Lepomis host specificity may be related to host hybridization. Posthodiplostomum species also differed in their utilization of host tissues. Neither common species displayed strong genetic structure over the scale of this study, likely due to their utilization of bird definitive hosts.

Experimental Investigation on Magnetic Field Effects of IPT for Electric Bikes

The wireless power transmission (WPT) is increasingly representing a promising technology and an innovative solution, especially for the electric vehicles (EVs) battery charging. The inductive power transfer (IPT) is the standard technology of wireless charging: the energy transfer occurs between two magnetically coupled coils. The IPT-based battery charging is especially convenient for E-bikes and the physiological effects related to the generated magnetic fields should be estimated. In this context, this work presents a 200 W prototype of wireless battery charger for E-bikes. In addition, the measurements regarding the surrounding magnetic field are given in detail in order to evaluate the actual physiological compatibility of the system.

Comparison of the Quality of Chitin and Chitosan from Shrimp, Crab and Squilla Waste

Chitin and Chitosan obtained from the crustaceans are having more biological value such as physiological compatibility, non-toxicity, bio digestibility, adsorption and chelating capacity. These biological values of chitosan depend on the quality parameters which are directly related to the source of the raw material. In this study, three commercially available crustacean shell waste such as shrimp, crab and squilla were used for the extraction of chitin and chitosan. The chemical treatment of demineralization, deproteinization and deacetylation were used for the production of chitosan. The viscosity quality parameter of the shrimp chitosan (5300cPs) was better than the crab and squilla chitosan. It is due the high solubility (97.65%) of the shrimp chitosan in 1% acetic acid. The degree of deacetylation of the shrimp chitosan (81.24%) directly relates the solubility of the chitosan. The chitosan with these quality parameters considered to be the excellent biological value. The yield of shrimp chitosan (15.4%) was also more when compare to crab and squilla chitosan. These result showed that utilisation of shrimp shell waste for the production of chitin and chitosan will give more economical and biological value along with reduction of environmental pollution.

Recent Progress toward Microfluidic Quality Control Testing of Radiopharmaceuticals.

Radiopharmaceuticals labeled with short-lived positron-emitting or gamma-emitting isotopes are injected into patients just prior to performing positron emission tomography (PET) or single photon emission tomography (SPECT) scans, respectively. These imaging modalities are widely used in clinical care, as well as in the development and evaluation of new therapies in clinical research. Prior to injection, these radiopharmaceuticals (tracers) must undergo quality control (QC) testing to ensure product purity, identity, and safety for human use. Quality tests can be broadly categorized as (i) pharmaceutical tests, needed to ensure molecular identity, physiological compatibility and that no microbiological, pyrogenic, chemical, or particulate contamination is present in the final preparation; and (ii) radioactive tests, needed to ensure proper dosing and that there are no radiochemical and radionuclidic impurities that could interfere with the biodistribution or imaging. Performing the required QC tests is cumbersome and time-consuming, and requires an array of expensive analytical chemistry equipment and significant dedicated lab space. Calibrations, day of use tests, and documentation create an additional burden. Furthermore, in contrast to ordinary pharmaceuticals, each batch of short-lived radiopharmaceuticals must be manufactured and tested within a short period of time to avoid significant losses due to radioactive decay. To meet these challenges, several efforts are underway to develop integrated QC testing instruments that automatically perform and document all of the required tests. More recently, microfluidic quality control systems have been gaining increasing attention due to vastly reduced sample and reagent consumption, shorter analysis times, higher detection sensitivity, increased multiplexing, and reduced instrumentation size. In this review, we describe each of the required QC tests and conventional testing methods, followed by a discussion of efforts to directly miniaturize the test or examples in the literature that could be implemented for miniaturized QC testing.

Lyophilisation and concentration of chitosan/siRNA polyplexes: Influence of buffer composition, oligonucleotide sequence, and hyaluronic acid coating

Chitosan (CS)/siRNA polyplexes have great therapeutic potential for treating multiple diseases by gene silencing. However, clinical application of this technology requires the development of concentrated, hemocompatible, pH neutral formulations for safe and efficient administration. In this study we evaluate physicochemical properties of chitosan polyplexes in various buffers at increasing ionic strengths, to identify conditions for freeze-drying and rehydration at higher doses of uncoated or hyaluronic acid (HA)-coated polyplexes while maintaining physiological compatibility. Optimized formulations are used to evaluate the impact of the siRNA/oligonucleotide sequence on polyplex physicochemical properties, and to measure their in vitro silencing efficiency, cytotoxicity, and hemocompatibility. Specific oligonucleotide sequences influence polyplex physical properties at low N:P ratios, as well as their stability during freeze-drying. Nanoparticles display greater stability for oligodeoxynucleotides ODN vs siRNA; AT-rich vs GC-rich; and overhangs vs blunt ends. Using this knowledge, various CS/siRNA polyplexes are prepared with and without HA coating, freeze-dried and rehydrated at increased concentrations using reduced rehydration volumes. These polyplexes are non-cytotoxic and preserve silencing activity even after rehydration to 20-fold their initial concentration, while HA-coated polyplexes at pH∼7 also displayed increased hemocompatibility. These concentrated formulations represent a critical step towards clinical development of chitosan-based oligonucleotide intravenous delivery systems.

Chickpea WRKY70 Regulates the Expression of a Homeodomain-Leucine Zipper (HD-Zip) I Transcription Factor CaHDZ12, which Confers Abiotic Stress Tolerance in Transgenic Tobacco and Chickpea.

Drought and salinity are the two major environmental constraints that severely affect global agricultural productivity. Plant-specific HD-Zip transcription factors are involved in plant growth, development and stress responses. In the present study, we explored the functional characteristics and regulation of a novel HD-Zip (I) gene from chickpea, CaHDZ12, in response to water-deficit and salt-stress conditions. Transgenic tobacco lines over-expressing CaHDZ12 exhibited improved tolerance to osmotic stresses and increased sensitivity to abscisic acid (ABA). Physiological compatibility of transgenic lines was found to be more robust compared to the wild-type plants under drought and salinity stress. Additionally, expression of several stress-responsive genes was significantly induced in CaHDZ12 transgenic plants. On the other hand, silencing of CaHDZ12 in chickpea resulted in increased sensitivity to salt and drought stresses. Analysis of different promoter deletion mutants identified CaWRKY70 transcription factor as a transcriptional regulator of CaHDZ12 expression. In vivo and in vitro interaction studies detected an association between CaWRKY70 and CaHDZ12 promoter during stress responses. Epigenetic modifications underlying histone acetylation at the CaHDZ12 promoter region play a significant role in stress-induced activation of this gene. Collectively, our study describes a crucial and unique mechanistic link between two distinct transcription factors in regulating plant adaptive stress response.

Enhancing Stent Effectiveness with Nanofeatures.

Drug-eluting stents are an effective therapy for symptomatic arterial obstructions, substantially reducing the incidence of restenosis by suppressing the migration and proliferation of vascular smooth muscle cells into the intima. However, current drug-eluting stents also inhibit the growth of endothelial cells, which are required to cover the vascular stent to reduce an excessive inflammatory response. As a result, the endothelial lining of the lumen is not regenerated. Since the loss of this homeostatic monolayer increases the risk of thrombosis, patients with drug-eluting stents require long-term antithrombotic therapy. Thus, there is a need for improved devices with enhanced effectiveness and physiological compatibility towards endothelial cells. Current developments in nanomaterials may enhance the function of commercially available vascular devices. In particular, modified design schemes might incorporate nanopatterns or nanoparticle-eluting features that reduce restenosis and enhance re-endothelialization. The intent of this review is to discuss emerging nanotechnologies that will improve the performance of vascular stents.

Stress-induced variation in host susceptibility to parasitic freshwater mussel larvae

An increasing number of studies demonstrate the critical role of the host–parasite relationship for the persistence and distribution of freshwater mussels. Laboratory experiments are a powerful tool for quantifying the physiological compatibility between parasitic mussel larvae and fish hosts and are clearly applicable to species conservation. Recent findings, however, indicate potential need to control for biases caused by infection intensity and host stress responses. We tested glochidia metamorphosis success and host plasma cortisol response using Lampsilis siliquoidea glochidia on Lepomis macrochirus. The main aims were to (1) compare metamorphosis success in response to infection intensity (number of attached glochidia per fish) and (2) compare metamorphosis success between typical and reduced-stress approaches to the handling and infection of host fish. We found no effect of the glochidia bath density used to infect the fish (1000–4000–8000 glochidia l−1) or the resulting infection intensity on metamorphosis success, although host plasma cortisol was correlated with infection intensity at 24 h post infection. Small but statistically significant differences in metamorphosis success were observed between the typical and reduced-stress approaches. Overall, typical host compatibility testing methods appear to be robust to these variables, but more emphasis on standardizing laboratory protocols may provide more repeatable data.

Fabrication and characterization of novel polyvinylpyrrolidone nanocomposites having SiO2 nanoparticles modified with citric acid and L(+)-ascorbic acid

Polyvinylpyrrolidone (PVP) is a synthetic polymer with high physiological compatibility, so incorporation a non-toxic nano-fller within the PVP as the polymer matrix to prepare novel nanocomposites (NC)s leads to bio-safe products for different applications. Therefore, silica nanoparticle (SNP) was chosen as an appropriate nano-filer to insert in the PVP matrix. Surface modification of SNPs was performed to prevent them from agglomeration and make them more compatible with the PVP matrix. Citric acid and vitamin C are two biological molecules which were used as modifiers. After surface treating of SNPs, different weight percentages (3, 5 and 7) of modified SNPs (M-silica) were added to the PVP and PVP/SiO2 NCs were prepared. The prepared NCs were examined using several techniques. The FESEM and TEM observations showed good compatibility of M-silica with the PVP matrix. From histogram diagrams the average particle size of M-silica in PVP matrix was estimated 30–40 nm.

Effect of TiO2 on photocatalytic activity of polyvinylpyrrolidone fabricated via electrospinning

Polyvinylpyrrolidone (PVP) is a promising material for electrospinning, and it has many desirable properties, including solubility in various solvents, physiological compatibility, chemical inertness, and excellent film-forming ability. Polymer–matrix composites of PVP–carbon fibers containing TiO2 were prepared via electrospinning. Degradation of environmental pollutants by the electrospun webs was evaluated based on methylene blue degradation. The optimum photocatalytic activity was achieved with webs containing 7 wt% TiO2. The results show that the proposed method is effective for improving the photocatalytic properties of TiO2-doped nanofibers; the doping process also increased the nanofiber surface area.

Restoring the ON Switch in Blind Retinas: Opto-mGluR6, a Next-Generation, Cell-Tailored Optogenetic Tool.

Photoreceptor degeneration is one of the most prevalent causes of blindness. Despite photoreceptor loss, the inner retina and central visual pathways remain intact over an extended time period, which has led to creative optogenetic approaches to restore light sensitivity in the surviving inner retina. The major drawbacks of all optogenetic tools recently developed and tested in mouse models are their low light sensitivity and lack of physiological compatibility. Here we introduce a next-generation optogenetic tool, Opto-mGluR6, designed for retinal ON-bipolar cells, which overcomes these limitations. We show that Opto-mGluR6, a chimeric protein consisting of the intracellular domains of the ON-bipolar cell–specific metabotropic glutamate receptor mGluR6 and the light-sensing domains of melanopsin, reliably recovers vision at the retinal, cortical, and behavioral levels under moderate daylight illumination.

Some Perspectives on the Problems and Prospects of Women Education, Empowerment and Gender Role in Nigeria

This paper highlights the need for psychological, physiological and dispositional compatibility of Women and the ability to enhance their human resourcefulness and empowerment through the acquisition and use of the ‘right’ type of education. The process of the acquisition and use of education, it is believed, can only come about through an understanding of the causal and physiological linkages between the nature and application of education, empowerment and the various roles expected from each gender. Just knowing the education-empowerment -gender role relationships might not be enough without knowing more and appraising the relationship that ought to work among these three concepts. This paper focuses on the ongoing concerns about education in Nigeria with regards to it's links with the acquisition by Women as well as their empowerment and gender roles. It further examines the rather artificial euphoric concerning the participation of Women in specific and more patriarchal professions and therefore creating a vacuum in feminine and important social roles. Finally, some recommendations were given on realignment of women education to enhance their natural roles using education as a tool. DOI: 10.5901/mjss.2014.v5n26p66

Antagonistic control of a dual-input mammalian gene switch by food additives.

Synthetic biology has significantly advanced the design of mammalian trigger-inducible transgene-control devices that are able to programme complex cellular behaviour. Fruit-based benzoate derivatives licensed as food additives, such as flavours (e.g. vanillate) and preservatives (e.g. benzoate), are a particularly attractive class of trigger compounds for orthogonal mammalian transgene control devices because of their innocuousness, physiological compatibility and simple oral administration. Capitalizing on the genetic componentry of the soil bacterium Comamonas testosteroni, which has evolved to catabolize a variety of aromatic compounds, we have designed different mammalian gene expression systems that could be induced and repressed by the food additives benzoate and vanillate. When implanting designer cells engineered for gene switch-driven expression of the human placental secreted alkaline phosphatase (SEAP) into mice, blood SEAP levels of treated animals directly correlated with a benzoate-enriched drinking programme. Additionally, the benzoate-/vanillate-responsive device was compatible with other transgene control systems and could be assembled into higher-order control networks providing expression dynamics reminiscent of a lap-timing stopwatch. Designer gene switches using licensed food additives as trigger compounds to achieve antagonistic dual-input expression profiles and provide novel control topologies and regulation dynamics may advance future gene- and cell-based therapies.

Herbonanoceuticals: A New Step Towards Herbal Therapeutics

Herbs and herbal derivatives are of great research interest owing to their wide applications in therapeutics. Several folk evidences have been recorded in the formulations of ancient world’s medicinal system, which have attracted researchers for their scientific validation. Various herbal compounds has been identified and showed their therapeutic efficiency against pathophysiological conditions. Employing these herbal compounds for synthesizing nanoparticles for biomedical applications have been ventured in recent times. Green synthesis is the procedure of synthesizing nanoparticles from herbal/ biogenic resources and several metallic nanoparticles have been synthesized by this process. The metal nanoparticle-herb combination may show better efficacy against different pathophysioloical conditions. This review tries to put forward the different metal nanoparticles formed from different herbal resources and their role in health and diseases. Although green synthesis of nanoparticle is an emerging area of research but very few data are available regarding their physiological effects, compatibility and toxicity. This review is an effort to elaborate in detail the role of medicinally important herbs in synthesizing metal nanoparticles, their physiological compatibility and therapeutic efficacy. Further, considerations and discussions are also made on limitations (toxicity) of the green synthesis of nanoparticles along with their future prospects in health and diseases. This review opens door to a completely new dimension in medicinal plant research combining the nanotechnology with herbs i.e. Herbonanoceuticals.