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PubMed2000

Production and dispersal of Colletotrichum gloeosporioides spores on Stylosanthes scabra under elevated CO2.

This paper reports the effect of twice-ambient (700 ppm) atmospheric CO(2) concentration on infection, disease development, spore production and dispersal of the anthracnose pathogen Colletotrichum gloeosporioides in susceptible (Fitzroy) and partially resistant (Seca) cultivars of the tropical pasture legume Stylosanthes scabra under controlled environment and field conditions. Reduction in plant height due to anthracnose was partially compensated for by growth enhancement at elevated CO(2) in Fitzroy but not in Seca. Anthracnose severity was reduced under elevated CO(2) although the reduction was only significant in Fitzroy. Delayed and reduced germination, germtube growth and appressoria production were partly responsible for the reduced severity. Despite an extended incubation period, C. gloeosporioides developed sporulating lesions faster and produced more spores per day within the same latent period at high CO(2) and ambient CO(2). When Fitzroy seedlings grown at 700 ppm CO(2) were exposed to pathogen inoculum under field conditions, they consistently developed more severe anthracnose with more lesions than seedlings grown at ambient CO(2). The environmental variable, which correlated most strongly with the dispersal and infection of C. gloeosporioides spores in the field, was relative humidity in plant canopy. We have shown that an enlarged Stylosanthes canopy under elevated CO(2) can trap more spores, which can lead to more severe anthracnose under favorable weather. The implications of these findings for perennial Stylosanthes pastures are discussed.

Journal Article↗

PubMed2001

Photosynthesis and biomass allocation of radish cv. "Cherry Belle" in response to root temperature and ozone.

To determine if ozone (O3) and root zone temperature (RZT) affect plant biomass allocation and photosynthesis, radish (Raphanus sativus) plants were grown in controlled environment laboratory chambers in one of four treatments: episodic O3 (average delivery 0.063 mumol mol-1) with RZT at 13 degrees C, episodic O3 (same delivery) with RZT at 18 degrees C, charcoal-filtered air with RZT at 13 degrees C and charcoal-filtered air with RZT at 18 degrees C. O3 reduced total biomass and shoot biomass of radish at 13 degrees C RZT but had no effect at 18 degrees C RZT. Low (13 degrees C) RZT decreased total biomass in both O3 and charcoal-filtered air. RZT had no overall effect on biomass allocation, but O3 lowered root-to-shoot ratios for plants grown at 18 degrees C RZT. Photosynthesis was reduced for plants grown at 18 degrees C RZT and O3, but stomatal conductance was not affected by O3 nor RZT. These results indicate that O3 and low RZT decrease biomass, but that plant photosynthesis is decreased by O3 and warm RZT.

Air Pollutants↗

PubMed1998

Epidemiology studies in immunotoxicity evaluations.

Studies in humans designed to detect immunomodulation from exposure to xenobiotics present challenging problems to epidemiologists and immunotoxicologists. Exposed and control groups must be carefully selected, exposure to the xenobiotic must be sufficiently high and well-documented, and the referent group should be as similar as possible to the exposed. Immune markers/functional tests in an individual may be influenced by sunlight exposure, medication, illness and use of recreational drugs; all of these potential confounding factors must be addressed. Sample acquisition is usually performed at sites geographically distant from the controlled environment of an investigator's laboratory, yielding an assortment of new problems that would not occur in clinical or hospital situations. Regulations and guidelines concerning the transport of biological samples and potential hazards of HIV and HBV exposures to personnel must be adapted to field conditions. Since the application of immunotoxicological techniques to populations exposed to xenobiotics is relatively new, and the ability to measure an increasing number of immune biomarkers of activation, suppression, autoimmunity or hypersensitivity is rapidly expanding, there are difficulties in the interpretation of statistically positive results (sometimes within the normal range) and their potential health significance. Finally, both biological and methodological factors complicate the assessment of dose-response/concentration effect relationships in human immunotoxicity studies, and traditional dose-response relationships may not always be present.

Drug Evaluation↗

PubMed2000

Evidence of social effects on mate choice in vertebrates.

Study of determinants of mate selection by animals has a long history in evolutionary biology and behavioural ecology. However, only during the past decade have investigators begun to conduct experiments exploring the various ways in which observation of the behaviour of others might influence mate selection. Here, we review both field and laboratory studies of behavioural processes that underlie non-independence in mate choice, discussing both direct and indirect social influences on mate selection. We focus on laboratory studies in which guppies and Japanese quail, species that have received greatest attention from investigators, have served as subjects. Although much is now known about how public information can affect mate selection in controlled environments, there are still significant gaps in our knowledge of whether and how such information contributes to mate selections by members of free-living populations.

Journal Article↗

PubMed2001

Identification and detection of Actinobacillus pleuropneumoniae by PCR based on the gene apxIVA.

The apxIVA gene, a recently discovered RTX determinant of Actinobacillus pleuropneumoniae, was shown to be species-specific. DNA hybridization experiments using probes for various regions of apxIVA revealed that the 3'-terminus of this gene was present in all 14 serotypes of A. pleuropneumoniae but absent from phylogenetically related species. A primer pair spanning this region specifically amplified a 422bp fragment in PCR experiments with DNA from the reference strains of the 14 serotypes and 194 field strains isolated from various geographic locations worldwide. DNA sequence analysis of PCR products derived from all serotypes were identical except in serotypes 3, 8, and 10, which showed minor differences. The PCR did not amplify any product when DNA from 17 different bacterial species closely related to A. pleuropneumoniae was used as template. In addition, the PCR was negative with DNA of several Actinobacillus sp. which were initially characterized as A. pleuropneumoniae using routine phenotypic and serological analyses but which were subsequently shown by 16S rRNA sequence analysis to belong to yet undefined Actinobacillus species. The sensitivity of the PCR was determined to be 10pg of A. pleuropneumoniae DNA. A set of nested primers amplified a 377bp fragment specifically with A. pleuropneumoniae DNA. DNA titration experiments using the flanking and nested primer pairs showed an improved level of sensitivity to approximately 10fg of genomic DNA. The nested PCR was used to monitor the spread of A. pleuropneumoniae in pigs experimentally infected with a virulent serotype 1 strain and housed in a controlled environment facility. A. pleuropneumoniae DNA could be detected by nested PCR in nasal swab samples of infected pigs receiving either a high dose (5x10(5)) or a low dose (1x10(4)) challenge and in unchallenged cohorts that were contact-infected by the inoculated animals. Furthermore, PCR confirmed the presence of A. pleuropneumoniae in 16/17 homogenates from necrotic lung lesions, while the bacterium was successfully recovered from 13 of these lesions by culture.

Actinobacillus Infections↗

PubMed1997

Contribution of the scrotum, testes, and testicular artery to scrotal/testicular thermoregulation in bulls at two ambient temperatures.

The objective of this study was to determine the contribution of the scrotum, testes, and the testicular artery to scrotal/testicular thermoregulation in bulls at two ambient temperatures. Crossbred beef bulls, 1.5 years of age, were placed in controlled environment chambers at ambient temperatures of 15 degrees C (n = 5) or 25 degrees C (n = 6). The distal lateral aspects and entire ventral part of the scrotum was incised under caudal epidural anaesthesia (xylazine, 0.07 mg kg-1. Both testes were withdrawn from the scrotum and then replaced and maintained by clamping the scrotal incisions with towel clamps. One testis was randomly chosen to be the exposed testis and was withdrawn prior to temperature measurements. Surface and internal temperature were measured with infrared thermography and needle thermocouples, respectively. Temperature gradients (degree C; difference in temperature from top to bottom at 15 and at 25 degrees C) were: scrotal surface (with testis), 1.5 and 1.3; scrotal surface (without testis), 2.1 and 1.6; surface of exposed testis, -0.6 and 0.0; sub-tunic of exposed testis, -2.2 and -0.6; intratesticular (covered testis), 0.0 and 0.4; and intratesticular (exposed testis), -1.3 and 0.4. The scrotum markedly affects testicular temperature but the testes have limited influence on scrotal surface temperature. The bovine scrotum and testes have opposing temperature gradients that complement one another, resulting in a relatively uniform intratesticular temperature. These temperature gradients are attributed in part to the testicular artery, which goes from the top of the testis to the bottom, divides into several branches and ramifies dorsally and laterally before entering the testicular parenchyma. Intra-arterial temperatures (measured with needle thermocouples) were lower (P < 0.05) where the artery entered the testis than at both the bottom and top of the testis for both the covered (31.7, 33.4 and 34.3 degrees C) and exposed testis (29.6, 32.0 and 32.5 degrees C) at an ambient temperature of 15 degrees C. Temperature differences were similar, but less pronounced, at 25 degrees C (covered testis, 34.8, 36.3 and 36.5 degrees C; exposed testis, 32.4, 33.5, 33.9 degrees C). Results supported the hypothesis that blood within the testicular artery has a similar temperature at the top of the testis (just ventral to the testicular vascular cone) compared with the bottom, but subsequently cools before entering the testicular parenchyma.

Animals↗

PubMed2000

The novel combination of dynamic vapour sorption gravimetric analysis and near infra-red spectroscopy as a hyphenated technique.

The novel combination of an environmental controlled gas flow microbalance (Dynamic Vapour Sorption, Surface Measurement Systems, UK) with a NIR spectrometer (Foss NIR Systems) is described. The study follows the gravimetric changes and the spectroscopic changes in the amorphous and crystalline states of lactose at 298 K. NIR spectra and gravimetric water sorption were recorded simultaneously for the same sample. Differentiation of the amorphous and crystalline states of lactose was possible from the evaluation of peak intensity and shifts in the known fingerprint regions of the NIR spectra, i.e. 1350-1510 and 1825-1975 nm which correspond to water changes, and 2075-2160 nm which tends to illustrate changes in the organic/structural backbone character. Gravimetric analysis confirmed that the amorphous lactose crystallised, as weight changes can be linked to structural changes. The combined technique maintains the high performance of the DVS microbalance for gravimetric analysis but also provides a preset, regulated and controllable environment for studies using NIR spectroscopy probes, which was previously not possible. The results obtained agree with accepted data, and therefore provide validation for the hyphenation technique. The use of the combined DVS-NIR instrument has indicated two new pieces of information, firstly the amorphous form loses some water before the crystallisation is detectable. This indicates that water desorption may precede crystallisation, rather than the other way around, and secondly, the sample has completed crystallisation before water desorption has ended.

Crystallization↗

PubMed1997

Tourette syndrome. Clinical rating and quantitative assessment of tics.

An adequate rating scale for the measurement of tic severity must account for the multiple motor and phonic tics that increase and decrease over time. Available rating scales for Tourette syndrome have used historical information, direct observation, or both. Videotapes provide an objective means to quantify tics over time in a controlled environment. Videotapes also can be viewed multiple times for careful review of tic frequency and distribution. A unified rating scale, which integrates all elements of tic assessment is being developed, but is not currently available.

Humans↗

PubMed1999

Circadian and ultradian rhythms of body temperature and peripheral concentrations of insulin and nitrogen in lactating dairy cows.

To investigate possible circadian and ultradian periodicities for peripheral insulin and urea in lactating dairy cows, integrated 15-min blood samples were taken sequentially over 48 hr from six cows. In addition, radiotelemetry measurements of body temperature were averaged over the same 15-min periods. Cows were housed in an environmental chamber at 19 degrees C with lights on 0700 to 2300 hr; fed daily at 0900 hr; and milked at 0800 and 2000 hr. For five of the six cows, body temperature showed a circadian rhythm peaking at 2323 hr with an amplitude of 0.34 degree C. For the sixth cow, body temperature was 180 degrees out-of-phase, peaking at 1230 hr with an amplitude of 0.12 degree C. Circadian rhythms for insulin and urea were consistent for all six cows peaking at 1743 hr with an amplitude of 0.74 ng/ml for insulin and at 1034 hr with an amplitude of 3.83 mM for urea. Body temperature and insulin also displayed episodic increases that often exceeded the amplitudes of circadian rhythms. For body temperature, a broad increase in spectral power was seen for periods between 100 and 175 min; time intervals between peaks averaged around 100 min. For insulin, power spectra for individual cows universally indicated rhythms with periods of approximately 45 and 80 min; time intervals between peaks averaged approximately 65 min. For urea, almost all spectral energy was confined to the 24-hr rhythm, although there was evidence of a low-amplitude, 60-min rhythm. In conclusion, when animals are acclimated to a rigidly controlled environment and frequent blood sampling is accomplished with minimal intervention, it is possible to detect rhythms inherent in the regulation of metabolic variables.

Animals↗

PubMed1997

Phosphorylation and proteolysis: partners in the regulation of cell division in budding yeast.

The budding yeast cell cycle oscillates between states of low and high cyclin B/cyclin-dependent kinase (CLB/CDK) activity. Remarkably, the two transitions that link these states are governed by ubiquitin-mediated proteolysis. The transition from low to high CLB activity is triggered by degradation of the CLB/CDK inhibitor SIC1, and the complementary excursion is propelled by the proteolytic destruction of CLBs. The extracellular environment controls this two-state circuit by regulating G1 cyclin/CDK activity, which is directly required for SIC1 proteolysis. Thus, stable oscillations of chromosome replication and segregation in budding yeast are propagated by the interplay between protein phosphorylation and protein degradation.

Cell Division↗

PubMed1996

Studies into aromatase activity associated with fetal allantochorionic and maternal endometrial tissues of equine placenta. Identification of metabolites by gas chromatography mass spectrometry.

Maternal endometrial and fetal allantochorionic tissues were separated manually from the placentae of seven healthy thoroughbred and three pony mares, ranging in gestational age from 100 to 318 days. The homogeneity of subcellular fractions prepared from these tissues was assessed initially using the marker enzymes, succinate dehydrogenase, NADPH cytochrome C reductase and lactate dehydrogenase for the mitochondrial, microsomal and cytosolic fractions, respectively. Light microscopy and histochemical analysis demonstrated that the separated fetal allantochorionic membrane, which is made up of allantoic and chorionic epithelia, contained no significant contamination of maternal tissues. The maternal endometrium, however, was found to contain appreciable amounts of fetal chorion torn off during the separation process. Tissue homogenates and subcellular fractions were incubated with testosterone together with [4-(14)C] and [(2)H5 or (2)H3] labelled analogues in either an NADPH (1 mM) or a NADPH-regenerating environment; control experiments (without additional cofactor) were also performed. After extraction of the tissue homogenates, neutral and phenolic (oestrogen) unconjugated steroids were separated by column chromatography. Radiolabelled studies revealed that in allantochorionic tissue incubations 67-77% of testosterone was converted to oestrogenic material, subcellular fractionation indicating that oestrogen production was largely confined to the microsomal fraction and time-course studies showing that the rate of formation appeared to be linear up to 90 min. In contrast, only 5-25% conversion occurred using maternal endometrial tissues, which could be accounted for by the contaminating presence of fetal chorion. No oestrogen production was detected in control incubations. These radiolabelled studies demonstrate that aromatase activity is located on the fetal allantochorionic surface and, together with the histochemical data, further delineate this activity to the chorion in mature equine placenta. Gas chromatographic-mass spectrometric (GC-MS) analysis of the phenolic extracts from allantochorionic tissue homogenate incubations indicated the presence of substrate-derived oestradiol-17beta (E2), 6-oxo-oestradiol-17beta (6-oxo-E2) and 6beta-hydroxyoestradiol-17beta (6beta-OH-E2). Whereas all three oestrogens were identified as metabolites from testosterone in incubations performed using allantochorionic tissue homogenates and post-mitochondrial suspensions (PMS), only E2 was identified from incubations performed using microsomal fractions prepared from this tissue. We conclude that both the microsomal and cytosol fractions are required for the conversion of E2 to the 6-oxygenated species in vitro. Using stable isotope-labelled substrates and GC-MS analysis the mechanism of formation of these metabolites from these in vitro incubation studies may be inferred. GC-MS analysis of the neutral extracts from allantochorionic tissue homogenate incubations confirmed the presence of small quantities of substrate-derived 5(10)-oestrenediols. No substrate-derived 5(10)-oestrene-3,17-diols were detected in extracts from microsomal preparations incubated in the absence of cytosol. These data suggest that demethylation of C19 steroids to produce C18 neutral steroids may require the synergistic action of enzymic activities that appear to reside both in the microsomal and cytosolic fractions of equine allantochorionic tissues.

Allantois↗

PubMed2001

Solid-gas reactions of complex oxides inside an environmental high-resolution transmission electron microscope.

In a gas reaction cell (GRC), installed in a high-resolution transmission electron microscope (HRTEM) (JEOL 4000EX), samples can be manipulated in an ambient atmosphere (p<50mbar). This experimental setup permits not only the observation of solid-gas reactions in situ at close to the atomic level but also the induction of structural modifications under the influence of a plasma, generated by the ionization of gas particles by an intense electron beam. Solid state reactions of non-stoichiometric niobium oxides and niobium tungsten oxides with different gases (O2, H2 and He) have been carried out inside this controlled environment transmission electron microscope (CETEM), and this has led to reaction products with novel structures which are not accessible by conventional solid state synthesis methods. Monoclinic and orthorhombic Nb(12)O(29) crystallize in block structures comprising [3x4] blocks. The oxidation of the monoclinic phase occurs via a three step mechanism: firstly, a lamellar defect of composition Nb(11)O(27) is formed. Empty rectangular channels in this defect provide the diffusion paths in the subsequent oxidation. In the second step, microdomains of the Nb(22)O(54) phase are generated as an intermediate state of the oxidation process. The structure of the final product Nb(10)O(25), which consists of [3x3] blocks and tetrahedral coordinated sites, is isostructural to PNb(9)O(25). Microdomains of this apparently metastable phase appear as a product of the Nb(22)O(54) oxidation. The oxidation reaction of Nb(12)O(29) was found to be a reversible process: the reduction of the oxidation product with H(2) results in the formation of the starting Nb(12)O(29) structure. On the other hand, the block structure of Nb(12)O(29) has been destroyed by a direct treatment of the sample with H(2) while NbO in a cubic rock salt structure is produced. This in situ technique has also been applied to niobium tungsten oxides which constitute the solid solution series Nb(8-n)W9(+n)O47 with 0< or =n< or =4. All of these phases crystallize in the threefold tetragonal tungsten bronze (TTB) superstructure of Nb(8)W(9)O(47) (n=0). In the main reaction, these phases decompose in a gas plasma (O2, H2 or He, p=20mbar) into WO(3-x), which evaporates and solidifies again near the irradiated crystallite, and (Nb,W)(24)O(64), which crystallizes in a 2a superstructure of the TTB type observed here for the first time in the system Nb-W-O. Nb(8)W(9)O(47), Nb(7)W(10)O(47) and Nb(6)W(11)O(47) always react in this way, independent of the applied gas. On the other hand, the treatment of Nb(5)W(12)O(47) (n=3) and Nb(4)W(13)O(47) (n=4) in an oxygen atmosphere often caused a different reaction: these phases have been oxidized and a heavily disordered bronze-type structure has been formed. The oxygen excess in these products is largely accommodated in segregated domains of WO(3).

Journal Article↗

PubMed1999

The pursuit of effective neuroprotection during infant cardiac surgery.

Advances in infant cardiac surgery have resulted in a dramatic decline in mortality rates; however, neurological morbidity remains an important concern. The effectiveness of a number of interventional strategies to prevent or minimize brain injury during open heart surgery are currently being investigated. This article provides an overview of two approaches: (1) interventions to enhance intraoperative cerebral oxygenation so as to prevent hypoxic-ischemic insults, and (2) the application of cerebral rescue therapies to attenuate the cascade of brain injury. Infant cardiac surgery provides a controlled environment in which to apply these neuroprotective approaches, so as to optimize the quality of life of these vulnerable children.

Acid-Base Imbalance↗

PubMed2004

C-terminal SRC kinase controls acute inflammation and granulocyte adhesion.

To establish whether the widely expressed regulator of Src family kinases Csk contributes to the control of acute inflammation in vivo, we inactivated csk in granulocytes by conditional mutagenesis (Cre/loxP). Mutant mice (Csk-GEcre) developed acute multifocal inflammation in skin and lung. Animals were protected from the disease in a microbiologically controlled environment, but remained hypersensitive to LPS-induced shock. Csk-deficient granulocytes showed enhanced spontaneous and ligand-induced degranulation with hyperinduction of integrins. This hyperresponsiveness was associated with hyperadhesion and impaired migratory responses in vitro. Hyperphosphorylation of key signaling proteins such as Syk and Paxillin in mutant granulocytes further supported breakdown of the activation threshold set by Csk. By enforcing the need for ligand engagement Csk thus prevents premature granulocyte recruitment while supporting the motility of stimulated cells through negative regulation of cell adhesion.

Acute Disease↗

PubMed2003

The hazards and prevention of driving while sleepy.

In the present paper the literature bearing on the association between sleepiness and driving is reviewed and the current state of prevention is discussed. Sleepiness may be a factor in about 20% of motor vehicle accidents and studies carried out in controlled environments suggest that the most common changes in driving performance attributable to sleepiness include increased variability of speed and lateral lane position. Higher-order functions including judgement and risk taking may also deteriorate. Moreover, prolonging wakefulness even by a few hours may produce deterioration in driving performance comparable to that seen in drivers with blood alcohol concentrations at levels deemed dangerous by legislation. The majority of prevention efforts to date have focussed on short-term solutions that only mask underlying sleepiness and it is suggested that more emphasis be directed toward primary prevention efforts such as educating drivers about the importance of getting sufficient sleep and avoiding circadian performance troughs. Finally, the important role that health professionals can play in the identification, treatment, and education of sleepy drivers is highlighted.

Accidents, Traffic↗

PubMed2001

Disease model: familial adenomatous polyposis.

Mutations in the APC gene are responsible for familial adenomatous polyposis (FAP) and for the majority of sporadic colorectal cancers. The establishment of genotype-phenotype correlations in FAP is often complicated by the great clinical variability observed among carriers of the same APC mutation even within the same kindred. This variability is likely to arise from the interaction of genetic and environmental modifying factors, the dissection of which ideally requires the employment of mouse models where the effects of specific Apc mutations are analyzed in an inbred, homogeneous genetic background and a controlled environment. The availability of different Apc mouse models allows not only the establishment of more precise genotype-phenotype correlations but has also provided very important clues for the understanding of the function of APC in homeostasis and tumorigenesis. Also, the close phenotypic resemblance to the human disease makes these mice unique preclinical models to test chemopreventive and therapeutic interventions.

Adenomatous Polyposis Coli↗

PubMedDate not supplied

Bio-based polymeric composites comprising wood flour as filler.

The increasing effort on development of bio-based polymeric materials in recent years is motivated by the basic concept of meeting the sustainability criteria for industrial development in the third millennium. Within this framework, our research group is currently involved in assessing the potentiality of some agro-industrial overproduction and byproducts in the formulation of eco-compatible bio-based polymeric materials displaying, among others, the propensity to biodegrade under controlled environment conditions. In the present work, beech wood flour (Bwf) composites were prepared from plasticized poly(3-hydroxybutyrate) (PHB). The type of plasticizer [tri(ethylene glycol) bis(2-ethylhexanoate) (TEGB) and poly(ethylene glycol) (PEG200)] and the amount [5 and 20 wt %] were selected as independent variables in a factorial design. Thermal and mechanical properties of 90 wt % PHB composites were investigated. Incorporation of PEG200 was found to compromise thermal stability of PHB as demonstrated by the higher decrease on the onset decomposition temperature (T(d)) and the drop in its average molecular weight (M(w)). The present study underlines the fact that TEGB/PHB/beech wood flour composites can be optimized to obtain new materials for disposable items.

Biodegradation, Environmental↗

PubMed2006

Real-time assessment of spatial and temporal coupled catalysis within polyelectrolyte microcapsules containing coimmobilized glucose oxidase and peroxidase.

The encapsulation of biological enzymes within polyelectrolyte microcapsules is an important step toward microscale devices for processing and analytical applications, one which could be applied to the realization of minimally invasive sensing technology. In this work, the encapsulation and functional characterization of a bienzymatic coupled catalytic system within polyelectrolyte microcapsules is described. The two components, glucose oxidase (GOx) and horseradish peroxidase (HRP), were coprecipitated with calcium carbonate microspheres, followed by layer-by-layer assembly to form ultrathin polymer film coatings that act as capsule walls after removal of the sacrificial carbonate cores. Encapsulated concentrations of GOx and HRP were determined to be 19.7 +/- 1.0 and 29.4 +/- 3.6 mg/mL, respectively. An 85% decrease in the rate of glucose consumption relative to GOx and HRP in free solution was observed, which is attributed to substrate diffusion limitations. To further understand the temporal and spatial dynamics of the two-step reaction, a technique for monitoring microscale glucose consumption was developed using confocal imaging techniques. Time-based acquisition of capsule/Amplex Red suspensions was performed, from which it was observed that the high concentration of enzyme immobilized within the capsule walls resulted in a greater rate and quantity of glucose consumption at the capsule periphery when compared to glucose consumption within the capsule interior. These findings demonstrate the function of a bienzymatic catalytic system within the controlled environment of polyelectrolyte microspheres and a novel approach to analysis of the internal reactions using confocal imaging that will allow direct comparison with reaction-diffusion modeling and further explorations to optimize the distribution and activity of the encapsulated species.

Aspergillus niger↗