Passive Immobilization Research Articles

3D-Printed Bioreceptive Tiles of Reaction–Diffusion (Gierer–Meinhardt Model) for Multi-Scale Algal Strains’ Passive Immobilization

The current architecture practice is shifting towards Green Solutions designed, produced, and operated domestically in a self-sufficient decentralized fashion, following the UN sustainability goals. The current study proposes 3D-printed bioreceptive tiles for the passive immobilization of multi-scale-length algal strains from a mixed culture of Mougeotia sp., Oedogonium foveolatum, Zygnema sp., Microspora sp., Spirogyra sp., and Pyrocystis fusiformis. This customized passive immobilization of the chosen algal strains is designed to achieve bioremediation-integrated solutions in architectural applications. The two bioreceptive tiles following the reaction-diffusion, activator-inhibitor Grier–Meinhardt model have different patterns: P1: Polar periodic, and P2: Strip labyrinth, with niche sizes of 3000 µm and 500 µm, respectively. The results revealed that P2 has a higher immobilization capacity for the various strains, particularly Microspora sp., achieving a growth rate 1.65% higher than its activated culture density compared to a 1.08% growth rate on P1, followed by P. fusiformis with 1.53% on P2 and 1.3% on P1. These results prove the correspondence between the scale and morphology of the strip labyrinth pattern of P2 and the unbranched filamentous and fusiform large unicellular morphology of the immobilized algal strains cells, with an optimum ratio of 0.05% to 0.75% niche to the cell scale. Furthermore, The Mixed Culture method offered an intertwining net that facilitated the entrapment of the various algal strains into the bioreceptive tile.

A Green Biocomposite Produced by Passive Cell Immobilization onto Waste Biomass Support for Biodecolorization of Reactive Dye Contamination

AbstractThe waste biomass of grape pomace was utilized for the immobilization of model fungal cells (Thamnidium elegans) providing a green, innovative, and practical biocomposite for efficient biodecolorization of a model reactive dye (Reactive Yellow 2). Appreciable decolorization capacity at optimized conditions was observed as qmax=151.0 mg g‐1 with the suggested biocomposite (TECWGP). During the batch process, the biocomposite exhibited the highest dye removal of 98.57 % in the RY2‐contaminated solutions. The biosorptive decolorization process was the best predicted by the Langmuir isotherm and the pseudo‐second‐order kinetic models. The possible interactions between RY2 and TECWGP were also examined. Synthetic wastewater treatment experiments indicated that TECWGP has a good decolorization potential. Overall, the findings indicated that TECWGP could be a good alternative to synthetic materials for the treatment of reactive dye‐contaminated aqueous phase. Furthermore, the utilization of agro‐industrial waste to support fungal cells contributes to the growth of a solid circular bio‐based economy.

Effect of passive cell immobilization of co-cultured yeasts on the whey fermentation and alcohols production

Whey is one of the main residues of the dairy industry and its valorization by fermentation is an emergent practice that contributes to the circular economy and sustainable development. Whey fermentation with specialized yeast strains produces value-added biomolecules, such as fusel alcohols of high interest for the pharmaceutic, food and cosmetic industries due to their aromatic and flavor properties. The present study aimed to develop the whey fermentation with the yeasts Kluyveromyces marxianus and Debaryomyces hansenii immobilized on inert support, to increase cell density and 2-phenylethanol (2-PE) production. Biochar synthesized from wood feedstock, perlite and filter Kaldnes plastic rings were used as supports for the cell immobilization. They were selected based on their different nature and physical properties such as porous structure and rough surface, to study the effect of different supports on yeast biofilm development. Also, functional groups such as hydroxyl, carbonyl, siloxane, and aliphatic hydrocarbons were useful for the development of covalent bonds and electrostatic forces between cells-support. The yeast immobilization increased the 2-PE production, especially on the plastic rings and perlite, obtaining 0.56 ± 0.01 g/L of 2-PE for the suspended culture and up to 0.91 ± 0.01 g/L for the immobilized co-culture on filter Kaldnes plastic rings.

Development of a streptavidin-bridged enhanced sandwich ELISA based on self-paired nanobodies for monitoring multiplex Salmonella serogroups

Salmonella are major pathogens that cause foodborne diseases. In this work, a broad-spectrum Salmonella nanobody-01 (Nb-01) was isolated and applied in the development of a streptavidin-bridged sandwich ELISA (SAB-ELISA) for simultaneously identifying five Salmonella serovars, including Salmonella Enteritidis (S. Enteritidis), Salmonella Typhimurium (S. Typhimurium), Salmonella London (S. London), Salmonella Paratyphi B (S. Paratyphi B) and Salmonella Hadar (S. Hadar). In this work, streptavidin (SA) was utilized as a scaffold to directionally immobilize biotinylated nanobody (BiNb) and Salmonella was detected by phage-displayed nanobodies. The SAB-ELISA can be accomplished within 180 min with a limit of detection (LOD) of 6.31 × 103 colony forming units (CFU) mL−1, 9.15 × 103 CFU mL−1, 4.23 × 103 CFU mL−1, 7.31 × 103 CFU mL−1 and 7.25 × 103 CFU mL−1 towards S. Typhimurium, S. Enteritidis, S. London, S. Paratyphi B and S. Hadar, respectively. In comparison of sandwich ELISA by passive immobilization of Nb-01 on polystyrene plate, the sensitivity was increased by around 6-fold, which confirmed the enhanced immobilization efficacy of SAB-ELISA. Furthermore, the feasibility of the assay for S. Typhimurium determination in actual samples was evaluated, showing excellent recovery, inter-day and intra-day precision.

An In Vivo Microfluidic Study of Bacterial Load Dynamics and Absorption in the C. elegans Intestine.

Caenorhabditiselegans (C. elegans) has gained importance as a model for studying host-microbiota interactions and bacterial infections related to human pathogens. Assessing the fate of ingested bacteria in the worm’s intestine is therefore of great interest, in particular with respect to normal bacterial digestion or intestinal colonization by pathogens. Here, we report an in vivo study of bacteria in the gut of C. elegans. We take advantage of a polydimethylsiloxane (PDMS) microfluidic device enabling passive immobilization of adult worms under physiological conditions. Non-pathogenic Escherichia coli (E. coli) bacteria expressing either pH-sensitive or pH-insensitive fluorescence reporters as well as fluorescently marked indigestible microbeads were used for the different assays. Dynamic fluorescence patterns of the bacterial load in the worm gut were conveniently monitored by time-lapse imaging. Cyclic motion of the bacterial load due to peristaltic activity of the gut was observed and biochemical digestion of E. coli was characterized by high-resolution fluorescence imaging of the worm’s intestine. We could discriminate between individual intact bacteria and diffuse signals related to disrupted bacteria that can be digested. From the decay of the diffuse fluorescent signal, we determined a digestion time constant of 14 ± 4 s. In order to evaluate the possibility to perform infection assays with our platform, immobilized C. elegans worms were fed pathogenic Mycobacterium marinum (M. marinum) bacteria. We analyzed bacterial fate and accumulation in the gut of N2 worms and mitochondrial stress response in a hsp-6::gfp mutant.

Attached culture of Gibberella fujikuroi for biocomposite sorbent production and ciprofloxacin sequestration applications

AbstractBACKGROUNDThe fluoroquinolone antibiotics in water sources are significant threats to public health, as well as the water ecosystem and water reuse. In this study, the feasibility of the biosorption of ciprofloxacin (CIP) using pine needles biomass‐Gibberella fujikuroi immobilized biocomposite (PNGFB) was promoted. It was prepared by passive cell immobilization onto the lignocellulosic matrix. The suggested biosorbent was characterized by Fourier Transform Infrared (FTIR) analysis, Scanning Electron Microscope (SEM), and zeta potential analysis. Series of batch and continuous mode experiments were conducted.RESULTSThe results of both systems showed that the PNGFB was effectively used for the treatment of CIP contamination. The maximum uptake occurred at pH 6.0, 40 min contact time, 1.0 mL min−1 flow rate, and 0.10 g (batch) and 0.20 g (column) PNGFB dosages. Redlich–Peterson isotherm model was the best suited to equilibrium data and the pseudo‐second‐order model predicted the biosorption kinetics. The maximum monolayer biosorption capability was 39.17 mg g−1. The suggested biocomposite also reached CIP removal yields of 64.14% and 53.74% in synthetic hospital effluent and synthetic urine samples containing 100 mg L−1 antibiotic, respectively. The regeneration study indicates that PNGFB retained its high biosorption and desorption yields during five cycles of the biosorption‐desorption.CONCLUSIONThe findings clearly showed that the PNGFB seems to be an eco‐friendly, effective, economic, and potentially viable biocomposite sorbent for the sustainable removal of CIP contamination. © 2021 Society of Chemical Industry (SCI).

Application of Printer Toner As a Versatile Intermediate for Protein Immobilization in Flexible Immunosensing Platforms

Introduction For the last years, low-cost microfluidics and microarrays on polyester substrates have gained applications in a variety of fields, including analytical Po int-of- C are systems. The use of a 2D platforms brings a significant reduction in assay costs, both due to a lower consumption of materials and reagents, as well as a simplicity of manufacturing process in comparison to current approaches [1]. Commercial applicability of immunoassays requires the development of efficient strategies for antibody immobilization in bulk quantities on a wide variety of readily available substrates. Other factors, which influence the usefulness of antibody immobilization approach are scalability, reproducibility and cost-efficiency. Simple, one-step methods such as passive adsorption on hydrophobic surfaces or direct protein immobilization with the use of functionalized silanes are particularly appreciated in fabrication of immunosensing platforms [2]. The use of masking properties of cured toner as an intermediate for passive and covalent immobilization of antibodies on poly(ethylene terephtalate) (PET) seems to be an attractive and still undiscovered path for development of immunoassays on versatile, printable substrates [3]. Fabricatio n of t oner-based platforms for Ab-capturing an d immunosensing Throughout presented research two general approaches for immobilization of antibody and antibody-binding protein (protein A/G) were examined: 1) adsorption on pristine PET@toner foil via hydrophobic interactions, 2) amine-dependent, covalent binding on glycidyloxypropyl tromethoxysilane (GTPMS)- coated surface. Print pattern (at various grayscale levels) was designed in ChemSketch 2.0 and printed on PET surface using HP 100 LaserJet P1006 printer at resolution of 1200 dpi. Pristine PET@toner foils were used for passive adsorption. For GTPMS coating, hydrophilization of toner was performed by a 10-minute treatment with the use of UV/ozone cleaner. Then, 3% GTPMS solution in 50% ethanol was dispensed on freshly-oxidized foil for 30 min. Both multi-purpose substrates characterized by different surface properties were then incubated with rabbit anti-CRP antibody or protein A/G followed by surface blocking. Method To fully characterize the analytical performance in a role of immunosensing platforms, two types of immunoreactions were carried out on prepared 2D Ab/protein arrays. Direct immuno-labelling of rabbit anti-CRP antibody with anti-rabbit IgG-alkaline phosphatase (ALP) conjugate aimed at comparative evaluation of specificity and efficiency of antibody coating. Indirect sandwich immunoassay for C-reactive protein was selected as a model to determine basic working parameters of toner-based immunoassay. Antibody-capturing properties of protein A/G surface were evaluated by determination of monoclonal antibody-ALP conjugate binding capacity. For quantitative analysis, enzymatic reaction was carried out by dispensing p-nitrophenyl phosphate as chromogenic ALP substrate. Results and Conclusions Results of immunolabeling confirmed the usefulness of cured toner as an intermediate for efficient antibody and protein A/G coating via hydrophobicity-driven adsorption. Due to an increase of surface area and a hydrophobicity higher than for pristine PET, the densest layers were observed for fully printed surfaces (100% black level). The differences in the surface properties were also reflected in kinetics of antibody binding. UV/ozone treatment resulted in permanent oxidation and thus hydrophilization of toner surface. The introduction of hydroxyl groups favored reaction with GTPMS. Epoxy-silane coating of oxidized toner enabled a rapid fabrication of protein-reactive surface characterized by a high binding capacity in a single step immobilization. Thanks to good adhesion and thus tight bonding of laser-cut adhesive tape to PET@toner, the microchannel architecture was obtained. It opened up the possibility to carry out immunoassays in microfluidic systems. It was proven that presented methodologies, due to the design and fabrication simplicity, use of commonly available materials and up-scalability, could be successfully applied in immunodiagnostics or flexible microfluidics for Lab-on-a-Foil technology.

Immobilized Mucor plumbeus on sepiolite support: A potential decolorization agent suitable for batch and continuous mode water treatment

This study was focused on the design of a new and effective decolorization agent by immobilization of Mucor plumbeus cells on the sepiolite matrix (MPSP). The passive immobilization method was used to attach the microbial cells to sepiolite. Methyl violet (MV) decolorization performance of this immobilized material was examined through batch and dynamic flow sorption studies. Biosorption of MV onto MPSP was characterized by using IR, SEM, EDX, and zeta potential analysis. MPSP achieved 89.60% decolorization performance under the optimum batch conditions. Langmuir isotherm model was found as the best-fitted model for the equilibrium data of MV biosorption. The highest monolayer sorption capacity of MPSP was 187.76 mg g−1. Sorption kinetics followed the pseudo-second-order model and the highest rate constant was recorded as 2.56 × 10−4 g mg−1 min−1 at 45 °C. Gibbs free energy (ΔG°) changed from −24.269 to −26.257 kJ mol−1 when the temperature was increased from 15 to 45 °C. Decolorization was identified as exothermic in nature (ΔH° = −5.176 kJ mol−1) and sorption reaction was accompanied by an increase in entropy (ΔS° = 0.066 kJ K−1 mol−1). IR analysis indicated that –OH and –CO groups played a role in the sorption. Fixed bed MPSP column showed almost 100% decolorization yield, good regeneration, and reusability potential. Although there are several studies conducted on the preparation of immobilized sorbent materials, this is the first study of the combined action of sepiolite and M.plumbeus cells for sorption purposes.

Microbial cells immobilized on natural biomatrix as a new potential ecofriendly biosorbent for the biotreatment of reactive dye contamination

Dye pollution in the aquatic environment is one of the main environmental and public health issue nowadays. Biosorptive removal of such dyes by biocomposite materials have recently emerged a good potential. For this purpose a novel microbial cell-immobilized Platanus orientalis leaf tissue (NSPOL) was prepared through a passive immobilization, in this study. Its bioremoval potential was investigated for Reactive Red 198 (RR198) and Reactive Yellow 2 (RY2) dyes at different conditions, including pH, biomaterial dosage, contact time and flow rate. Biosorption of RR198 and RY2 by NSPOL was found to be a fast process. Biosorption data were well predicted with the pseudo-second-order kinetic model for both dyes. Decolorization patterns fitted well with Langmuir isotherm model. Maximum monolayer biosorption capacities were recorded as 51.12 and 37.59 mg g−1 for RY2 and RR198, respectively. IR and SEM analysis revealed the biosorption of dyes onto biocomposite. Regeneration experiments showed that the biosorption performance of NSPOL was consistent towards RR198 and RY2 removal upto 5 recycles. After 5 biosorption-desorption cycles, the regeneration efficiency of NSPOL was still higher than 98 % for RY2 dye. Overall, batch and column studies indicated that suggested biocomposite may be a good and economic alternative for the removal of reactive azo dye contamination from aquatic media. Possible mechanism for biosorptive dye removal may be H-bonding, π−π and electrostatic interactions.

Polymer-Assisted Biocatalysis: Polyamide 4 Microparticles as Promising Carriers of Enzymatic Function

This study reports a new strategy for enzyme immobilization based on passive immobilization in neat and magnetically responsive polyamide 4 (PA4) highly porous particles. The microsized particulate supports were synthesized by low-temperature activated anionic ring-opening polymerization. The enzyme of choice was laccase from Trametes versicolor and was immobilized by either adsorption on prefabricated PA4 microparticles (PA4@iL) or by physical in situ entrapment during the PA4 synthesis (PA4@eL). The surface topography of all PA4 particulate supports and laccase conjugates, as well as their chemical and physical structure, were studied by microscopic, spectral, thermal, and synchrotron WAXS/SAXS methods. The laccase content and activity in each conjugate were determined by complementary spectral and enzyme activity measurements. PA4@eL samples displayed >93% enzyme retention after five incubation cycles in an aqueous medium, and the PA4@iL series retained ca. 60% of the laccase. The newly synthesized PA4-laccase complexes were successfully used in dyestuff decolorization aiming at potential applications in effluent remediation. All of them displayed excellent decolorization of positively charged dyestuffs reaching ~100% in 15 min. With negative dyes after 24 h the decolorization reached 55% for PA4@iL and 85% for PA4@eL. A second consecutive decolorization test revealed only a 5–10% decrease in effectiveness indicating the reusability potential of the laccase-PA4 conjugates.

Microfluidic Device for Microinjection of Caenorhabditis elegans.

Microinjection is an established and reliable method to deliver transgenic constructs and other reagents to specific locations in C. elegans worms. Specifically, microinjection of a desired DNA construct into the distal gonad is the most widely used method to generate germ-line transformation of C. elegans. Although, current C. elegans microinjection method is effective to produce transgenic worms, it requires expensive multi degree of freedom (DOF) micromanipulator, careful injection alignment procedure and skilled operator, all of which make it slow and not suitable for scaling to high throughput. A few microfabricated microinjectors have been developed recently to address these issues. However, none of them are capable of immobilizing a freely mobile animal such as C. elegans worm using a passive immobilization mechanism. Here, a microfluidic microinjector was developed to passively immobilize a freely mobile animal such as C. elegans and simultaneously perform microinjection by using a simple and fast mechanism for needle actuation. The entire process of the microinjection takes ~30 s which includes 10 s for worm loading and aligning, 5 s needle penetration, 5 s reagent injection and 5 s worm unloading. The device is suitable for high-throughput and can be potentially used for creating transgenic C. elegans.

Encapsulated behavior and extraction ability of uranium in coal ash: A quantitative investigation with SiO2-Al2O3-Fe2O3-CaO system

Uranium-rich coal ash (CA) receives much attention as the supplementary nuclear resource also its potential environmental risk. In this study, experiments were conducted to investigate the influences of major oxides on the U mobility in synthetic ash (SA) via sequential extraction and SiO2-Al2O3-Fe2O3-CaO system. Overall, modes of occurrence of U were governed by the complicated interactions among U and major oxides. Molten CaO could remarkably activate the refractory minerals and resulted in a large proportion of active U, while it was opposite for Fe2O3 due to the formation of amorphous Fe-Si depletion with the high strength. However, the activated and the encapsulated behaviors of U were both weakened if provided the sufficient Al2O3, by considering a passive immobilization of U in Si-Al matrix. Based on aforementioned facts, uranium mobility was synergistically controlled by various influences especially upon a medium SiO2 content. Ultimately, an equation, α = MCa/(MSi + MFe + MAl) + MAl/100, was established to describe the extracting ability of U from SA with a known composition. It is most efficient to extract U when α is 0.75 once the U-rich CA is employed to synthesize supplementary nuclear resources.

An impedimetric micro-immunosensing assay to detect Alzheimer's disease biomarker: Aβ40

A miniaturized biosensing platform, based on monoclonal amyloid-beta antibodies (mAβab) that were immobilized on a disc-shaped platinum/iridium (Pt/Ir) microelectrode surface coupled with an impedimetric signal transducer, was developed for the label-free and sensitive detection of amyloid-beta peptide fragment 1–40 (Aβ40); a reliable biomarker for early diagnosis of Alzheimer's disease (AD). A Pt/Ir microelectrode was electropolymerized with poly (ortho-phenylenediamine), a conducting free amine-containing aromatic polymer; followed by crosslinking with glutaraldehyde for subsequent coupling of mAβab on the microelectrode surface. This modification strategy efficiently improved the impedimetric detection performance of Aβ40 in terms of charge transfer resistance (∼400-fold difference) and normalized impedance magnitude percentage change (∼40% increase) compared with a passive adsorption-based immobilization method. The sensitivity of the micro-immunosensing assay was found to be 1056 kΩ/(pg/mL)/cm2 and the limit of detection was found to be 4.81 pg/mL with a dynamic range of 1−104 pg/mL (R2 = 0.9932). The overall precision of the assay, as measured by relative standard deviation, ranged from 0.84 to 5.15%, demonstrating its reliability and accuracy; while in respect to assay durability and stability, the immobilized mAβab were able to maintain 80% of their binding activity to Aβ40 after incubation for 48 h at ambient temperature (25 °C). To validate the practical applicability, the assay was tested using brain tissue lysates prepared from AD-induced rats. Results indicate that the proposed impedimetric micro-immunosensing platform is highly versatile and adaptable for the quantitative detection of other disease-related biomarkers.

Electrically Guided DNA Immobilization and Multiplexed DNA Detection with Nanoporous Gold Electrodes.

Molecular diagnostics have significantly advanced the early detection of diseases, where the electrochemical sensing of biomarkers (e.g., DNA, RNA, proteins) using multiple electrode arrays (MEAs) has shown considerable promise. Nanostructuring the electrode surface results in higher surface coverage of capture probes and more favorable orientation, as well as transport phenomena unique to nanoscale, ultimately leading to enhanced sensor performance. The central goal of this study is to investigate the influence of electrode nanostructure on electrically-guided immobilization of DNA probes for nucleic acid detection in a multiplexed format. To that end, we used nanoporous gold (np-Au) electrodes that reduced the limit of detection (LOD) for DNA targets by two orders of magnitude compared to their planar counterparts, where the LOD was further improved by an additional order of magnitude after reducing the electrode diameter. The reduced electrode diameter also made it possible to create a np-Au MEA encapsulated in a microfluidic channel. The electro-grafting reduced the necessary incubation time to immobilize DNA probes into the porous electrodes down to 10 min (25-fold reduction compared to passive immobilization) and allowed for grafting a different DNA probe sequence onto each electrode in the array. The resulting platform was successfully used for the multiplexed detection of three different biomarker genes relevant to breast cancer diagnosis.

Biotin-tagged proteins: Reagents for efficient ELISA-based serodiagnosis and phage display-based affinity selection.

The high-affinity interaction between biotin and streptavidin has opened avenues for using recombinant proteins with site-specific biotinylation to achieve efficient and directional immobilization. The site-specific biotinylation of proteins carrying a 15 amino acid long Biotin Acceptor Peptide tag (BAP; also known as AviTag) is effected on a specific lysine either by co-expressing the E. coli BirA enzyme in vivo or by using purified recombinant E. coli BirA enzyme in the presence of ATP and biotin in vitro. In this paper, we have designed a T7 promoter-lac operator-based expression vector for rapid and efficient cloning, and high-level cytosolic expression of proteins carrying a C-terminal BAP tag in E. coli with TEV protease cleavable N-terminal deca-histidine tag, useful for initial purification. Furthermore, a robust three-step purification pipeline integrated with well-optimized protocols for TEV protease-based H10 tag removal, and recombinant BirA enzyme-based site-specific in vitro biotinylation is described to obtain highly pure biotinylated proteins. Most importantly, the paper demonstrates superior sensitivities in indirect ELISA with directional and efficient immobilization of biotin-tagged proteins on streptavidin-coated surfaces in comparison to passive immobilization. The use of biotin-tagged proteins through specific immobilization also allows more efficient selection of binders from a phage-displayed naïve antibody library. In addition, for both these applications, specific immobilization requires much less amount of protein as compared to passive immobilization and can be easily multiplexed. The simplified strategy described here for the production of highly pure biotin-tagged proteins will find use in numerous applications, including those, which may require immobilization of multiple proteins simultaneously on a solid surface.

Functional Outcome and Complications of Open Reduction and Internal Fixation With Low-Profile Plates in Hand Fractures

Introduction: Fractures of the metacarpals and phalanges are common injuries that account for up to 40% of upper extremity fractures. Such fractures occur in the age range between 10 and 40 years, are more common in men, and have a particular association with sports. Although conservative treatment is presented as an alternative therapy, the results are not always satisfactory. Plate fixation has demonstrated superior over other surgical methods in repeated biomechanical and clinical studies. There has been published literature that proves low-profile plates have even fewer complications than other surgical techniques that are less aggressive such as percutaneous pinning. The aim of this study is the retrospective evaluation of the clinical results and complications of patients with fractures of metacarpals and phalanges treated by open reduction internal fixation with low-profile plates. Materials and Methods: A retrospective review of the patient database for the period 2003-2014 was performed. Seventy-two patients who met the inclusion criteria were obtained. We identified 62 male and 14 female patients. The average age was 30.62 years (range, 15-58 years). An injury in the dominant hand was identified in 34 patients. For metacarpal fractures, a dorsal metacarpal approach over the affected bone was performed. A longitudinal incision is made on the periosteum, with the aim of preserving bone vascularity. The plate was placed dorsally. In the case of fractures of the proximal phalanx, a dorsolateral approach was performed. Bone was exposed through a longitudinal approach on the periosteum. The plate was placed dorsolateral in all cases. Additional compression screws were placed as needed according to the fracture type. The immediate postoperative period includes a wound coverage with padded bandages associated with immobilization antebrachiopalmar in intrinsic plus position. Passive motion and active immobilization were initiated at first and third week, respectively. Results: The final range of motion as rated by Duncan was grade I in 42 patients, grade II in 16 patients, grade III in 11 patients, and grade IV in 3 patients. The proportion of grip strength averaged 81.3% compared with the contralateral side. The time to fracture healing was 2.3 months. Complications were described: 4 cases of hypertrophic scar and keloid, 2 cases of complex regional pain syndrome, 6 cases of delayed union, 1 patient had a case of refracture. No cases of infection associated with osteosynthesis material were observed. We found that fractures in nondominant hand, intra-articular fractures, and delay in surgical treatment are associated with poorer functional outcomes ( P < .05). Conclusion: The low-profile plates are valid for the treatment for metacarpal and phalangeal fractures. Progress in implant design has reduced the complications attributed to the material. However, the range of mobility and functional end complications depend largely on the presence or absence of factors associated with the patient, the fracture, and the circumstances. In this study, we have shown that the presence of lesions in nondominant hand, the intra-articular commitment, and delayed surgical treatment are factors associated to low-end range of functional mobility.

Plasmonic Nanohole Sensor for Capturing Single Virus-Like Particles toward Virucidal Drug Evaluation.

A plasmonic nanohole sensor for virus-like particle capture and virucidal drug evaluation is reported. Using a materials-selective surface functionalization scheme, passive immobilization of virus-like particles only within the nanoholes is achieved. The findings demonstrate that a low surface coverage of particles only inside the functionalized nanoholes significantly improves nanoplasmonic sensing performance over conventional nanohole arrays.

Student’s Perceptions about Pediatric Dental Behavior Guidance Techniques throughout a five-year Dental Curriculum

Objective: To compare students’ views about behavior management techniques (BMT) in pediatric dentistry, besides to identify whether educational components of dental curriculum may influence their perceptions. Material and Methods: Questionnaires with 18 statements, describing the techniques and clinical situations were distributed to students (n=83) from first- (P1), third- (P2) and eighth- (P3) semesters. Student’s acceptability scores were measured with a Likert scale from 0 (total disagreement) to 10 (total agreement). Statistical analysis was performed using Mann Whitney U test. Results: P3 students agreed with most of BMTs. Pair comparisons between P1-P2 showed significant increase of means for Told treatment may involve pain and Sedative, besides significant decrease for Use of euphemisms. Comparisons between P2-P3 and P1-P3 indicated significant increase in the acceptability for: Voice control, Told not to be coward, Modeling, Blunting, Use of euphemisms, Parent not present, HOME, Active and Passive Immobilization and pharmacologic techniques. In all semesters, Verbal positive reinforcement, Distraction and Tell-show-do were the most accepted techniques, however, there was no consensus regarding to the least accepted one. Promising a toy became less acceptable throughout the semesters and Parent not present became more acceptable. Conclusion: These findings indicate that educational process may influence on the students’ perceptions about BMTs.

P.1.g.060 Lithium as a new potential treatment for diabetic neuropathic pain; possible involvement of glycogen synthase kinase 3 beta

injected to cubs of both sexes from 5th to 7th days of life in doses of 0.01, 0.1, 1.0, and 10.0 mg/kg in a volume of 1 ml/10 g of body mass. This period is interpreted as a phase of active ontogeny of neural system (including vasopression components). The influence of peptide on animal depressive traits was scored on 63rd day of life using the standard Porsolt’s method of forced swimming. In the ‘forced swimming’ test, animals treated with an analog in all doses exhibited a decrease of depression behavioral components. In a group of animals treated with doses of 0.01 and 0.1mg/kg the significant increase of total duration of total immobilization time together with the decrease of immobilization time. In a group of animals treated with a dose of 1.0mg/kg the first period of active swimming was longer and occurred later, while number of both passive swimming and immobilization decreased. A dose of 10.0mg/kg appeared to be the most effective dose: almost all parameters in animals treated with this dose pointed at lower depression level in comparison with control animals. In all groups the decrease of immobilization time occurred via the prolonged total duration of passive swimming thus evidencing for an adaptogenous action of studied substance. No significant differences were found between animals of different sexes. The obtained results evidence for the fact that the early postnatal intranasal injection of original structural analog of fragment of arginine-vasopressin (6−9) in doses of 0.01, 0.1, 1.0, and 10.0mg/kg has prolonged positive influence on the behavioral adaptation and decreases animals’ depression in selected conditions. The given effect is observed on the 63rd day of animals’ life thus supporting an idea of prolonged effect of novel analog after its chronic injection during the first days of life. This phenomenon provides an opportunity to propose this analog’s effect on the processes of ontogeny of neural system.

Enhanced human lysozyme production in biofilm reactor by Kluyveromyces lactis K7

Lysozyme is an antimicrobial compound, which has been used in pharmaceutical and food industries. Chicken egg is the commercial source of lysozyme. However, human lysozyme is more effective and safer than egg-white lysozyme. Human milk is an important source for human lysozyme, but it is not feasible to provide the needed lysozyme commercially. Biofilm reactors provide passive immobilization of cells onto the solid support, which may lead to higher productivity. The aim was to evaluate the fermentation medium composition for enhanced human lysozyme production by Kluyveromyces lactis K7 in biofilm reactor with plastic composite supports. Yeast nitrogen base was selected as the best nitrogen source when compared to the yeast extract and corn steep liquor. Moreover, inhibition effect of NaCl and NH4Cl at the concentrations of 25 and 50mM was observed. Three factors Box–Behnken response surface design was conducted and the results suggested 16.3% lactose, 1.2% casamino acid, 0.8% yeast nitrogen base as optimum medium composition for maximum human lysozyme production. Overall, the human lysozyme production by K. lactis K7 was increased to 173U/ml, which is about 23% improvement in biofilm reactor and 57% improvement compared to the suspended-cell fermentation.