Mesoporous Silica Modified with Polydopamine and Zinc Ions as a Potential Carrier in the Controlled Release of Mercaptopurine.

Mercaptopurine is one of the drugs used in the treatment of acute lymphoblastic leukemia. A problem with mercaptopurine therapy is its low bioavailability. This problem can be solved by preparing the carrier that releases the drug in lower doses but over a longer period of time.

An Overview of the Potential Medicinal and Pharmaceutical Properties of Ru(II)/(III) Complexes.

This review examines the existing knowledge about Ru(II)/(III) ion complexes with a potential application in medicine or pharmacy, which may offer greater potential in cancer chemotherapy than Pt(II) complexes, which are known to cause many side effects. Hence, much attention has been paid to research on cancer cell lines and clinical trials have been undertaken on ruthenium complexes. In addition to their antitumor activity, ruthenium complexes are under evaluation for other diseases, such as type 2 diabetes, Alzheimer's disease and HIV.

Non-Covalent Isotope Effects.

In this Perspective, we present examples of isotope effects that originate from noncovalent interactions, mainly hydrogen bonding, electrostatics, and confinement. They are traditionally widely used in isotopic enrichment processes, as well as in studies of mechanisms of different (bio)chemical and physical phenomena. We then show the emerging areas of their applications, mainly medical and material sciences.

ScanMedicine: An online search system for medical innovation.

ScanMedicine is a novel searching system dedicated to providing health care professionals, patients, carers, the public, decision- and policy-makers, and researchers with open access to the development pipeline underpinning health technology innovations. In the first phase of developing ScanMedicine, we have focused on capturing and consolidating clinical trial records hosted on national and international clinical trials registries and medical device approval data from the FDA. ScanMedicine has been developed based on microservice architecture allowing the system to be constantly improved in a flexible and scalable manner.

Release of drugs used in the treatment of osteoporosis from zeolites with divalent ions-Influence of the type of ion and drug on the release profile.

Bisphosphonates are drugs that are used to treat osteoporosis that causes the low mineral density of the bones. These drugs can be delivered in several ways, but each method has disadvantages. Materials with high potential as carriers of these drugs are zeolites with divalent ions.

Environment-friendly transesterification to seawater-degradable polymers expanded: Computational construction guide to breaking points.

Marine plastic pollution caused by non-biodegradable polymers is a major worldwide concern. So-called "biodegradable" polymers should reduce plastic pollution in the environment by the safeguard of biodegradation. However, many polyesters degrade very slowly in seawater.

Unprecedently large Cl/Cl equilibrium isotopic fractionation on nano-confinement of chloride anion.

Confinement can result in unusual properties leading to new, exciting discoveries in the nano-realm. One such consequence of confinement at the nanoscale is extremally large isotopic fractionation, especially at sub-van der Waals distances. Herein, on the example of chlorine isotope effects, we show that at conditions of nanoencapsulation these effects may reach values by far larger than observed for the bulk environment, which in the case of nanotubes can lead to practical applications (e.

Can Adsorption on Graphene be Used for Isotopic Enrichment? A DFT Perspective.

We have explored the theoretical applicability of adsorption on graphene for the isotopic enrichment of aromatic compounds. Our results indicate that for nonpolar molecules, like benzene, the model compound used in these studies shows a reasonable isotopic fractionation that is obtained only for the deuterated species. For heavier elements, isotopic enrichment might be possible with more polar compounds, e.

The use of serine protease from Yarrowia lipolytica yeast in the production of biopeptides from denatured egg white proteins.

Deriving non-conventional enzymes from cheaper sources than those used for commercially available enzymes may result in the production of hydrolysates with beneficial features, while drastically reducing the cost of hydrolysis. This is especially significant for enzymatic hydrolysis as a method of protein waste utilization. We have previously described the ability of non-commercial serine protease from Yarrowia lipolytica yeast to produce/release bioactive peptides from egg white protein by-products (EP).

Multifunctional peptides derived from an egg yolk protein hydrolysate: isolation and characterization.

An egg yolk protein by-product following ethanol extraction of phospholipids (YP) was hydrolyzed with pepsin to produce and identify novel peptides that revealed antioxidant, ACE inhibitory and antidiabetic (α-glucosidase and DPP-IV inhibitory) activities. The peptic hydrolysate of YP was fractionated by ion-exchange chromatography and reversed-phase high-pressure liquid chromatography. Isolated peptides were identified using mass spectrometry (MALDI-ToF) and the Mascot Search Results database.

Egg-yolk protein by-product as a source of ACE-inhibitory peptides obtained with using unconventional proteinase from Asian pumpkin (Cucurbita ficifolia).

Unlabelled: In the present study angiotensin I-converting enzyme (ACE) inhibitory peptides were isolated from egg-yolk protein preparation (YP). Enzymatic hydrolysis conducted using unconventional enzyme from Cucurbita ficifolia (dose: 1000 U/mg of hydrolyzed YP (E/S (w/w)=1:7.52)) was employed to obtain protein hydrolysates.

Improving the properties of fodder potato protein concentrate by enzymatic hydrolysis.

Protein hydrolysates of profitable properties were prepared from the fodder potato protein concentrate. The hydrolysis process was performed with the use of commercial available enzyme (Alcalase) over a 2 and 4 h incubation period. Chemical and amino acid composition as well as functional properties of resultant hydrolysates were determined.

An attractive way of egg white protein by-product use for producing of novel anti-hypertensive peptides.

The aim of this study was to (i) examine how enzymatic hydrolysis with a non-commercially available proteinase of fig-leaf gourd fruit (Cucurbita ficifolia) increased the use value of egg white protein preparations, generated as byproducts in the industrial process of lysozyme and cystatin isolation from egg white, and (ii) evaluate the inhibition of angiotensin I-converting enzyme (ACE) by the obtained hydrolysates. Purification procedures including membrane filtration, gel filtration chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC) led to the production of several peptide fractions. Two novel ovalbumin-derived tetrapeptides: SWVE (f 148-151) and DILN (f 86-89) with ACE inhibitory activity were obtained.

Application of Asian pumpkin (Cucurbita ficifolia) serine proteinase for production of biologically active peptides from casein.

The main objective of this study was to determine potential application of a serine proteinase derived from Asian pumpkin for obtaining biologically active peptides from casein. The course of casein hydrolysis by three doses of the enzyme (50, 150, 300 U/mg of protein) was monitored for 24 hours by the determinations of: hydrolysis degree DH (%), free amino group content (μmole Gly/g), RP HPLC peptide profiles and by polyacrylamide gel electrophoresis. In all hydrolyzates analyzed antioxidant activities were determined using three tests: the ability to reduce iron ions in FRAP test, the ability to scavenge free radicals in DPPH test, and Fe(2+) chelating activity.

Biological and functional properties of proteolytic enzyme-modified egg protein by-products.

Enzymatic hydrolysis led to improve functional properties and biological activity of protein by-products, which can be further used as protein ingredients for food and feed applications. The effects of proteolytic enzyme modification of egg-yolk protein preparation (YP) and white protein preparation (WP), obtained as the by-products left during the course of lecithin, lysozyme, and cystatin isolation on their biological and functional properties, were evaluated by treating a commercial Neutrase. The antihypertensive and antioxidative properties of YP and WP hydrolysates were evaluated based on their angiotensin-converting enzyme (ACE)-inhibitory activity and radical scavenging (DPPH) capacity, ferric reducing power, and chelating of iron activity.

Susceptibility of adult rats to lead-induced changes in NMDA receptor complex function.

Because cognitive impairments can occur with occupational Pb exposures, changes in NMDA receptor complex function might be expected to occur in adult rats treated with Pb. Using drug discrimination procedures, MK-801 sensitivity was determined in adult rats at three time points: after chronic exposure to 0, 50, or 150 ppm Pb acetate; again after exposure levels were increased to 500 and 1000 ppm; and 6 months after termination of Pb exposure. Changes in blood (PbB) and brain Pb levels, and in MK-801 and CGP-39653 binding, were examined in additional groups of nonbehaviorally tested rats.

Preferential vulnerability of nucleus accumbens dopamine binding sites to low-level lead exposure: time course of effects and interactions with chronic dopamine agonist treatments.

This study examined the hypotheses that low-level lead (Pb) exposure would increase dopamine (DA) binding sites, would do so preferentially in nucleus accumbens, and that such effects would be modified by concurrent DA agonist treatment. D1-like and D2-like binding sites and the dopamine transporter (DT) were measured autoradiographically in caudate-putamen and nucleus accumbens of rats exposed from weaning to 0, 50, or 150 ppm Pb acetate drinking solutions with or without concurrent chronic intermittent intraperitoneal injections of the D1-like agonist SKF 82958 or the DA agonist apomorphine after 2 weeks (no injections), 8 months, or 12 months of Pb exposure. Pb selectively decreased DA binding in nucleus accumbens.

The effects of dopamine agonists on fixed interval schedule-controlled behavior are selectively altered by low-level lead exposure.

A previous report of differential effects of catecholaminergic compounds, but not other classes of compounds, on FI (fixed interval) response rates of lead (Pb)-treated pigeons suggests that catecholamine system disturbances might play a role in lead (Pb)-induced changes in FI performance. The current study sought to extend those findings using more selective dopaminergic (DA) D1 and D2-like receptor agonists, Pb-treated rats, and additional classes of compounds. Drug-induced changes in FI performance of rats exposed chronically from weaning to 0, 50, or 150 ppm Pb acetate in drinking water were compared following the administration of drugs known to impact various neurotransmitter systems altered by Pb exposure, including the selective D2-like agonist quinpirole, the D1 agonists SKF38393 and SKF82958, the mu-opioid agonist morphine, the muscarinic cholinergic agonist arecoline, the glutamate agonist NMDA, and the noncompetitive NMDA antagonist MK-801.

Postweaning lead exposure enhances the stimulus properties of N-methyl-D-aspartate: possible dopaminergic involvement?

This study sought to determine whether previously reported Pb-induced biochemical changes in the NMDA receptor complex also resulted in changes in NMDA sensitivity in vivo. Rats chronically exposed to 0, 50 or 150 ppm Pb acetate in drinking water postweaning were trained to discriminate the stimulus properties of 30 mg/kg NMDA from saline using standard operant food-reinforced drug discrimination procedures. Following acquisition of the discrimination, various doses of NMDA, of the competitive antagonist CPP, the D2 antagonist spiperone and the D1 antagonist SCH23390 were substituted for the NMDA training dose and percent NMDA responding to each determined.

Lead-induced changes in dopamine D1 sensitivity: modulation by drug discrimination training.

Prior studies have reported that Pb exposure results in enhanced sensitivity to both D1 and D2 dopamine agonists as indicated by left shifts of the dose-effect functions for the discrimination of these agonists from saline in drug discrimination procedures (Cory-Slechta and Widzowski, 1991). To further determine mechanisms of such Pb-induced changes in dopamine system functions, this study evaluated the potential contribution to Pb-induced D1 supersensitivity of:i) synergistic D1-D2 receptor interactions, and ii) the effects of the chronic D1 agonist administration inherent in the drug discrimination procedures themselves. As in Cory-Slechta and Widzowski (1991), rats exposed from weaning to 50 or 150 ppm Pb acetate in drinking water and trained using standard operant drug discrimination procedures to discriminate 6.

Lead-induced changes in muscarinic cholinergic sensitivity.

This study was undertaken to determine whether the biochemical changes in cholinergic systems produced by lead exposure result in corresponding changes in cholinergic sensitivity in vivo. Rats chronically exposed from weaning to 0, 50 or 150 ppm lead (Pb) acetate in drinking water were trained to discriminate the stimulus properties of a dose of 1.75 mg/kg of the muscarinic cholinergic agonist, arecoline, from saline, using standard operant food reinforced drug discrimination procedures.

Time course of postnatal lead-induced changes in dopamine receptors and their relationship to changes in dopamine sensitivity.

Although alterations in dopaminergic function represent a potential neurochemical basis of Pb-induced behavioral deficits, the impact of postnatal Pb exposure on DA systems has not been adequately delineated. This study examined the effects of postnatal Pb exposure, across a broad range of concentrations, on the ontogeny of both D1 and D2 DA (dopamine) receptors in striatum and nucleus accumbens. Rat pups were exposed to Pb from 0-21 days of age via lactating dams consuming solutions of 0, 100, 350, 1000 or 2000 ppm Pb acetate.

Functional alterations in dopamine systems assessed using drug discrimination procedures.

Numerous studies have suggested that Pb-induced perturbations of dopamine (DA) systems and DA functions could underlie the behavioral impairments attributed to Pb exposure. However, the precise nature of the effects of Pb on DA systems, either at the receptor/biochemical level or at the behavioral level have never been precisely delineated, much less interrelated. Substantial advances in the understanding of DA neuropharmacology provide new opportunities to more precisely elaborate Pb-induced changes in DA systems and DA function.

Postnatal lead exposure induces supersensitivity to the stimulus properties of a D2-D3 agonist.

To examine the impact of lead (Pb) exposure during the ontogeny of dopaminergic (DA) systems on resultant DA function, rats were exposed postnatally (0-21 days of age) via the lactating dam to 0, 100 or 350 ppm Pb acetate in drinking water. At 2 months of age, the postnatally Pb-exposed rats were trained to discriminate the stimulus properties of either the D1 receptor agonist SKF38393 (6.0 mg/kg) or the D2-D3 receptor family subtype agonist quinpirole (0.

Behavioral manifestations of prolonged lead exposure initiated at different stages of the life cycle: II. Delayed spatial alternation.

Since both Pb exposure and aging have been associated with alterations in memory functions, this study compared the effects of Pb exposure initiated at early, middle and later stages of the life cycle on delayed spatial alternation performance. Young (21 day old), adult (8 mon old) and old (16 mon old) rats were exposed for a total duration of 8.5 mon to 0, 2 or 10 mg Pb acetate/kg/day (young rats) or 0, 1.