Comparison of the mopping ability of chemically modified and unmodified biological wastes on crude oil and its lower fractions

Activated and unactivated powders of goat hair and coir (coconut husk) separated into two particle sizes were used to mop up spills of crude oil, diesel, kerosene and petrol. It was observed that the materials (sorbents) mopped up appreciable volumes of the hydrocarbon liquids (sorbates) within 90 min of contact. Activation, particle size of sorbents and molecular weight (chain length) of sorbates (hydrocarbon) are major determining factors. Carbonization and particle size enhanced the mopping ability as follows--carbonized 325 microm > uncarbonized 325 microm > carbonized 625 microm > uncarbonized 625 microm, thus activated sorbents with large surface area (small particle size) mopped more hydrocarbons than unactivated of the same particle size. The sorbates were mopped in the order--crude oil > diesel > kerosene > petrol. It was further observed that goat hair (keratin protein) with oleophilic and aquaphobic properties adsorbed more of all the hydrocarbons than coir at all sizes and treatment. Large quantities of the mopped oils were recovered by mere pressing while the waste sorbents with 0.5-2.0% leachable residual oil could be utilized as alternative to fire wood.     

Study of lipoprotein sorption by some sulfoderivatives of chitosan

The possibility of deposition of lipoproteins from blood plasma by different chitosan sulfoderivatives has been demonstrated. The influence of structure, substitution degree and molecular weight of chitosan sulfates on lipoprotein sorption was studied as well as the influence of composition of chitosan interpolymer complexes with dextransulfate. Affinic sorbents based on the silica matrixes and sulfoderivatives of chitosan as a ligand can reveal high specificity in relation to low density lipoprotein, but do not cause essential changes in blood count during contact with blood.     

Composite fluorine polymer-containing sorbents for isolation and purification of biopolymers

Composite fluoropolymer-containing sorbents based on porous silicas were synthesized for the isolation and purification of biopolymers under nondenaturing conditions. Examples of the application of these sorbents in the separation of various mixtures of peptides and proteins and purification of nucleic acids from various sources (plasmid DNA and DNA from nucleated human blood cells) using the cartridge, column, and batch (sorption in a stirred volume) methods are presented. It was shown that the sorbents can be used in laboratory practice because they are selective to nucleic acids (DNA and RNA) and proteins. These materials combine the mechanical properties of the inorganic matrix with the specific sorption properties of the polymer phase and exhibit enhanced stability to alkaline hydrolysis. Alternative methods of preparing sorbents containing polytetrafluoroethylene, polytrifluorostyrene, and polyfluorobutadiene are described. By the example of polyfluorobutadiene-containing sorbents, a completely new method for obtaining fluorinated polymer phases was developed: the polymer phase was preliminarily formed on the surface of porous disperse carriers and was fluorinated with xenon difluoride.     

Methods and prospects of development of the affinitive sorbents for plasminogen isolation from human blood plasma

The review paper was dedicated to development of the promising photochemical synthesis of affine sorbents for plasminogen isolation from the human blood plasma. Some most interesting, from the viewpoint of practice, types of sorbents and carriers based on high-molecular compounds of natural (organic) or synthetic origin have been considered. The advantages of the use of photochemical synthesis of biospheric sorbent as compared with thermochemical method have been shown. The most promising methods of creation of affine sorbents on the basis of oligomer-polymeric photoinitiators and oligomerpolymeric photosensibilizing (donor-acceptor) systems are presented.     

A new approach to the depletion of albumin and immunoglobulin G from human serum

The use of proteomic analysis to find potential diagnostic biomarkers is limited by the presence of serum albumin (HSA) and immunoglobulin (IgG) at high concentrations in patients’ blood; these substances impede the detection of serum proteins with similar molecular weights. Recombinant HSA- and IgG-binding polypeptides are used as ligands in creating sorbents for complete removal of the proteins by affinity chromatography. The binding specificity of the sorbents for HSA and IgG is higher than that of the conventionally used antibodies. A composite sorbent enabling the depletion of HSA and IgG from serum by single-step affinity chromatography was obtained. The developed sorbents were used to prepare serum for proteomic analysis.     

Study of the mechanism of interaction of antibody (IgG) on two mixed mode sorbents

Purification of target proteins from a crude biological mixture containing proteins, peptides and other biomolecules is the chromatographic challenge. Mixed mode chromatography offers additional selectivities to improve the overall productivity of commercial bioprocesses with novel chromatographic sorbents being introduced to overcome the problem. HEA HyperCel? (n-hexyl amine) and PPA HyperCel? (phenyl propyl amine) are industry scalable mixed mode chromatography sorbents where both hydrophobic and electrostatic interactions are predominant. Our study focuses on understanding the underlying mechanism of interaction of protein with the sorbent. Parameters like buffer conditions, pH and temperature were tuned to study the adsorption and desorption conditions of the protein. Dynamic binding capacity of HEA HyperCel? and PPA HyperCel? sorbents was studied with human IgG as a model protein. Our study shows that, in HEA the interaction of IgG to the sorbent is predominantly hydrophobic as the binding is enhanced (50–60 mg/ml of sorbent) by presence of salt in buffer and increase in temperature. Binding capacity of PPA is 50–60 mg/ml of sorbent irrespective of temperature effect and/or the presence of salt. The chromatographic experiments show that the interaction could be hydrophobic or ionic or some charge transfer mechanism depending upon the buffer conditions.     

Effect of perfluorocarbon emulsions on rheological parameters of blood

The effect of a perfluorocarbon emulsion on the rheological parameters of blood in a living organism at the hematocrit twice lower than the norm was studied. It was shown that an increase in emulsion concentration leads to an increase in blood asymptotic viscosity and the aggregation of erythrocytes. It was concluded that only a small volume of the fluorocarbon phase of particles, as compared with the total amount of erythrocytes, can improve the blood fluidity upon disturbed circulation.     

Evaluation of a Pet Program in Prison—The Pal Project at Lorton

Abstract

We studied a program that permitted a selected number of prisoners to keep pets. We observed the physiological and behavioral effects of this contact and retrospectively examined the effect of pet possession on the frequency and severity of disciplinary offenses. The presence of a pet did not affect the rise in blood pressure associated with talking to the experimenters. However, blood pressure during interaction with the pet was always lower than blood pressure during conversation with the experimenters. Pet ownership had a small effect on the number but not the severity of disciplinary offenses. We concluded that this pet program provided valuable recreation for prisoners but had only small and inconsistent effects on antisocial behavior as defined by the prison staff.     

Functional changes in the small intestine under the influence of sorbents in rats with a radiation-thermal lesion

Major small intestine functions of rats were inhibited after whole-body exposure to radiation and heat. The injection of sorbents varying in the chemical structure favored the recovery of the small intestine function.     

DNA aptamer-based sorbents for binding human IgE

DNA aptamer-based sorbents were synthesized for binding human IgE. Sorbents effectively removed IgE from human blood plasma. The experimental values of IgE desorption constants were within the range of 1.1 × 10^?10 to 1.7 × 10^?10 M depending on the orientation of the aptamer on an insoluble matrix. The sorbents were stable during multiple use. Conditions for sorbent regeneration were selected. These chromatographic materials can be used for medical and biotechnological applications.     

Removal of copper(II) using chitin/chitosan nano-hydroxyapatite composite

Polymeric composites made up of nano-hydroxyapatite (n-HAp) with chitin and chitosan have been prepared and studied for the removal of Cu(II) ions from the aqueous solution. The sorption capacity (SC) of n-HAp, n-HAp/chitin (n-HApC) composite and n-HAp/chitosan (n-HApCs) composite were found to be 4.7, 5.4 and 6.2 mg/g respectively with a minimum contact time of 30 min. Batch adsorption studies were conducted to optimize various equilibrating conditions like contact time, pH and selectivity of metal ion. The sorbents were characterized by FTIR, TEM, XRD and SEM with EDAX analysis. The sorption process was explained with Freundlich and Langmuir isotherms respectively. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated to understand the nature of sorption. A suitable mechanism for copper sorption was established and the selectivity of the metal ions for the composites was identified.     

Dependence of equilibrium and kinetic parameters of erythromycin: a sorption on the structural characteristics of the biosorbent

The use of special synthetic sorbents with surface carboxyl groups allowed us to increase fourfold the effective diffusion coefficient for erythromycin. The maximum sorption capacity for the antibiotic exceeded twofold that observed in experiments with a macroporous sulfocation exchanger MN-500. The sorption of the antibiotic was completely reversible upon treatment with a combined eluant that competitively interacts with the sorbent and does not impair the structural characteristics of erythromycin.     

Dependence of equilibrium and kinetic parameters of erythromycin a sorption on the structural characteristics of the biosorbent

The use of special synthetic sorbents with surface carboxyl groups allowed us to increase fourfold the effective diffusion coefficient for erythromycin. The maximum sorption capacity for the antibiotic exceeded twofold that observed in experiments with a macroporous sulfocation exchanger MN-500. The sorption of the antibiotic was completely reversible upon treatment with a combined eluant that competitively interacts with the sorbent and does not impair the structural characteristics of erythromycin.     

Lipid vesicle adsorption versus formation of planar bilayers on solid surfaces.

The absorption and spreading behavior of lipid vesicles composed of either palmitoyloleoylphosphatidylcholine (POPC) or Escherichia coli lipid upon contact with a glass surface was examined by fluorescence measurements. Fluorescently labeled lipids were used to determine 1) the amount of lipid adsorbed at the surface, 2) the extent of fusion of the vesicles upon contact with the surface, 3) the ability of the adsorbed lipids to undergo lateral diffusion, and 4) the accessibility of the adsorbed lipids by external water soluble molecules. The results of these measurements indicate that POPC vesicles spread on the surface and form a supported planar bilayer, whereas E. coli lipid vesicles adsorb to the surface and form a supported vesicle layer. Supported planar bilayers were found to be permeable for small molecules, whereas supported vesicles were impermeable and thus represented immobilized, topologically separate compartments.     

Histidine ligand affinity chromatography

The sorbents with immobilized histidine as a pseudo affinity ligand with a wide specificity is described. The possibilities and relevant chemistries to use both particulate and flat or hollow fiber membranes as support matrices are discussed. The usefulness of such adsorbents for the purification of a wide variety of proteins, with relevant interaction mechanism are described. Practical protocols of sample quality, capacity and scaled up and scaled down operations are discussed. Possibilities of pyrogen removal from high value blood proteins and their simultaneous recovery in the pure form, using histidine immobilized sorbents are described.     

Cutaneous blood flow and water absorption by dehydrated toads

Blood cell flux (BCF) in ventral pelvic skin capillaries was measured in toads, Bufo woodhouseii and Bufo punctatus, using a chamber that allowed hydration behavior and water absorption to be observed concurrently in unrestrained animals. Dehydrated B. woodhouseii and B. punctatus placed on a rehydration solution significantly increased BCF relative to that on a dry surface in less than 2 min. Skin contact with a rehydration solution rather than dehydration alone is the primary stimulus for increased seat patch blood flow. In B. woodhouseii, the water absorption response was initiated after the increase in BCF had started but before maximum BCF was reached. BCF and water uptake across the ventral skin of both species placed on deionized water were not different from those of toads placed on 50 mM NaCl. Similarly, no significant correlation between BCF and rate of water uptake could be observed in dehydrated toads of either species. Angiotensin II (AII) injection in hydrated B. punctatus had no effect on BCF, suggesting that factors other than AII are responsible for the increase in blood flow upon water contact in dehydrated toads.     

Differences in finger skin contact cooling response between an arterial occlusion and a vasodilated condition.

To assess the presence and magnitude of the effect of skin blood flow on finger skin cooling on contact with cold objects against the background of circulatory disorder risks in occupational exposures, this study investigates the effect of zero vs. close-to-maximal hand blood flow on short-term (< or =180 s) skin contact cooling response at a contact pressure that allows capillary perfusion of the distal pulp of the fingertip. Six male volunteers touched a block of aluminium with a finger contact force of 0.5 N at a temperature of -2 degrees C under a vasodilated and an occluded condition. Before both conditions, participants were required to exercise in a hot room for > or = 30 min for cutaneous vasodilation to occur (increase in rectal temperature of 1 degrees C). Under the vasodilated condition, forearm blood flow rate rose as high as 16.8 ml.100 ml(-1).min(-1). Under the occluded condition, the arm was exsanguinated, after which a blood pressure cuff was secured on the wrist inducing arterial occlusion. Contact temperature of the finger pad during the subsequent cold contact exposure was measured. No significant difference was found between the starting skin temperatures for the two blood flow conditions, but a distinct difference in shape of the contact cooling curve was apparent between the two blood flow conditions, with Newtonian cooling observed under the occluded condition, whereas a rewarming of the finger skin toward the end of the exposure occurred for the vasodilated condition. Blood flow was found to significantly increase contact temperature from 40 s onward (P < 0.01). It is concluded that, at a finger contact force compatible with capillary perfusion of the finger pad ( approximately 0.5 N), circulating blood provides a heat input source that significantly affects finger skin contact cooling during a vasodilated state.     

Blood reactions in vitro in crayfish against a fungal parasite, Aphanomyces astaci

The immediate and subsequent reactions in crayfish blood upon making contact with hyphae of the crayfish plague fungus were observed in vitro. Blood cells agglomerated and clumped rapidly on the hyphae in streaming blood. Very brief contact by chance with a hypha, or with cell extensions from cells or a cell clump on the hypha, caused flowing cells to stop and adhere. Chemotaxis was not believed to be of any importance. Particles originating from hemocyte granules were specifically attached to, and “encapsulated” the distal portion of, the hypha (even without the presence of the cells themselves), where their content of polyphenol oxidase became activated. These processes may be connected with the defense mechanism in crayfish. Within a few hours the process of melanization could be observed on the hyphal surface. Both the enzyme(s) and the substrate(s) for the melanization reaction seem to originate from the blood cells. Dihydroxyphenylalanine (DOPA) could replace the natural substrate and greatly enhanced the process. The melanization in whole blood was much heavier in a crayfish resistant to the disease than in a susceptible one.     

Growth cone-growth cone interactions in cultures of rat sympathetic neurons

Growth cones of sympathetic neurons from the superior cervical ganglia of neonatal rats were studied using video-microscopy to determine events following contact between growth cones and other cell surfaces, including other growth cones and neurites. A variety of behaviors were observed to occur upon contact between growth cones. Most commonly, one growth cone would collapse and subsequently retract upon establishing filopodial contact with the growth cone of another sympathetic neuron. Contacts resulting in collapse and retraction were often accompanied by a rapid and transient burst of lamellipodial activity along the neurite 30-50 microns proximal to the retracting growth cone. In no instances did interactions between growth cones and either fibroblasts or red blood cells result in the growth cone collapsing, suggesting that a specific recognition event was involved. On several occasions, growth cones were seen to track other growth cones, although fasciculation was rare. In some cases, there was no obvious response between contacting growth cones. Growth cone-growth cone contact was almost four times more likely to result in collapse and retraction than was growth cone-neurite contact (45% vs 12%, respectively). These observations suggest that the superior cervical ganglion may be composed of neurons with different cell surface determinants and that these determinants are more concentrated on the surface of growth cones than on neurites. These results further suggest that contact-mediated inhibition of growth cone locomotion may play an important role in growth cone guidance.     

Blood gas analysis: effect of air bubbles in syringe and delay in estimation.

Two common sources of error in blood pH and blood gas analysis were studied. The effect of delay in estimation was studied in 10 volunteers and 40 patients. Syringes were stored at 0 degree C, (crushed ice), 4 degrees C (refrigerator) and 22 degrees C (room temperature). The pressure of oxygen (PO2) fell significantly by 20 minutes at 4 degrees C and 22 degrees C but did not change significantly at 0 degree C for up to 30 minutes. Blood pH, pressure of carbon dioxide (PCO2), and base excess did not change significantly for up to 30 minutes at 4 degrees C and 22 degrees C and up to 60 minutes at 0 degrees C. The effect of air bubbles in the syringe was studied by leaving a single bubble or froth in contact with the blood for one to five minutes in 40 patients. Po2 rose significantly after two minutes'' contact with froth and two minutes'' contact with the air bubble, and PCO2 fell significantly after three minutes'' contact with the air bubble. Size of the bubble had little effect on rates of change. Blood pH, bicarbonate, TCO2, and base excess did not change significantly after up to five minutes'' contact. For accurate estimation of PO2 and PCO2 it is necessary to avoid frothing, to expel all air bubbles within two minutes, and to inject the sample into the machine within 10 minutes or store the syringe in crushed ice. The requirements for blood pH and base excess measurement are less exacting.