Initial Immobilization Research Articles

β-xylosidase from Selenomonas ruminantium: Immobilization, stabilization, and application for xylooligosaccharide hydrolysis

The tetrameric β-xylosidase from Selenomonas ruminantium is very stable in alkaline pH allowing it to easily immobilize by multipoint covalent attachments on highly activated glyoxyl agarose gels. Initial immobilization resulted only in slight stabilization in relation to the free enzyme, since involvement of all subunits was not achieved. Coating the catalyst with aldehyde-dextran or polyethylenimine, fully stabilized the quaternary structure of the enzyme rendering much more stabilization to the biocatalyst. The catalyst coated with polyethylenimine of molecular weight 1300 is the most stable one exhibiting an interesting half-life of more than 10 days at pH 5.0 and 50 °C, being, therefore, 240-fold more stable than free enzyme. Optimum activity was observed in the pH range 4.0–6.0 and at 55 °C. The catalyst retained its side activity against p-nitrophenyl α-l-arabinofuranoside and it was inhibited by xylose and glucose. Kinetic parameters with p-nitrophenyl β-d-xylopyranoside as substrate were Vmax 0.20 μmol.min−1 mg prot.−1, Km 0.45 mM, Kcat 0.82 s−1, and Kcat/Km 1.82 s−1 mM−1. Xylose release was observed from the hydrolysis of xylooligosaccharides with a decrease in the rate of xylose release by increasing substrate chain-length. Due to the high thermostability and the complete stability after five reuse cycles, the applicability of this biocatalyst in biotechnological processes, such as for the degradation of lignocellulosic biomass, is highly increased.

Patella fractures in knee arthroplasty

Periprosthetic patella fractures occur both with and without retropatellar joint replacement. Anon-operative treatment yields satisfactory results with low morbidity. It can be applied in minimally displaced fractures that have an intact retropatellar component and an intact extensor mechanism, combined with an initial immobilization. The surgical treatment is associated with relatively poor results and with high complication rates. There was only minor improvement of functional results, no matter which surgical technique was used. Surgical intervention is still required in fractures with aloosening of the patellar component, considerable dislocations of fragments, and damage to or rupture of the extensor mechanism. In particular, typeII fractures require repair of the extensor mechanism and the fracture or patellectomy. TypeIII fractures require arevision or resection of the patella, apatelloplasty or total patellectomy. In addition, early or late reconstruction using allograft to restore the extensor mechanism can be taken in consideration.

Patellar Dislocations and Reduction Procedure.

Acute patellar dislocations are a common injury occurring in adolescents involved in sports and dancing activities. This injury usually occurs when the knee is in full extension and sustains a valgus stress on the knee. The medial patellofemoral ligament is the medial restraint that assists in stabilizing the patella from lateral dislocations. The patella usually dislocates laterally and is usually not difficult to reduce after patient evaluation and prereduction radiographs. After postreduction radiographs confirm proper position of the patella postreduction and the absence of fractures, the patient is usually treated conservatively with initial immobilization, orthopedic referral, and physical therapy.

Fate of 15N-fertilizers in the soil-plant system of a forage rotation under conservation and plough tillage

For agriculture sustainability and biosphere conservation in the 21st century, to improve N use efficiency and to reduce the fertilization rates is fundamental. The N dynamics in the soil-plant system can be altered after the adoption of conservation practices, making necessary to evaluate the fertilizer efficiency and, if needed, to adapt N fertilization. Accordingly, during two years, we assess the effect of conventional plough tillage (PT) and conservation minimum tillage (MT) on the N dynamics in a 14-year-old ryegrass-maize forage rotation. We used a 15N-tracing approach to evaluate the recovery efficiency of N (REN) taking into account both the N immobilized in soil (0–5, 5–15, 15–30, 30–45 and 45–60cm) and that exported at harvest. Adjacent PT (n=9) and MT (n=9) plots were randomly assigned in triplicate to three treatments to which 15NH415NO3 (10 atom% 15N) was applied in one of the three first fertilizations (15NOctober-, 15NMarch- and 15NMay-fertilizer), the others being done with unlabelled N. Plant N concentration (% N) was affected (p<0.001; n=18) by the crop [80% of variance explained: ryegrass-1 (2.6±0.9%)>ryegrass-2 (1.9±0.4%)>maize-2 (1.4±0.1%)>maize-1 (1.1±0.2%)] and the crop-tillage interaction (22% of variance explained). Jointly considering all data, more 15N-fertilizer was recovered in the MT (25±4%) than in the PT soil profile (19±6%) at the end of the experiment whereas the N exported with the crops was unaffected by the tillage system and varied from 5–6% (15NOctober-fertilizer) to 45–49% (15NMarch-fertilizer) and 52–53% (15NMay-fertilizer; despite only three instead of four subsequent crops were studied).The 15N unaccounted for in the case of 15NOctober-fertilizer (72±5%) was more than twice that in 15NMarch- (34±7%) and 15NMay-fertilizer (25±14%). Considering soil, site and weather conditions, denitrification and nitrate leaching during the ryegrass-1 crop were the most likely processes explaining the high losses of the 15NOctober-fertilizer. Results suggested a higher initial immobilization of the applied 15N in the soil organic matter (SOM) of MT, that reduces 15N availability to the first crop, followed by an increase of the residual availability of the fertilizer 15N to the subsequent 2–3 crops.

Bio‐Inspired Renewable Surface‐Initiated Polymerization from Permanently Embedded Initiators

AbstractHerein, we describe a simple and robust approach to repeatedly modify surfaces with polymer brushes through surface‐initiated atomic transfer radical polymerization (SI‐ATRP), based on an initiator‐embedded polystyrene sheet that does not rely on specific surface chemistries for initiator immobilization. The surface‐grafted polymer brushes can be wiped away to expose fresh underlying initiator that re‐initiates polymerization. This strategy provides a facile route for modification of molded or embossed surfaces, with possible applications in the preparation of fluidic devices and polymer‐embedded circuits.

Bio-Inspired Renewable Surface-Initiated Polymerization from Permanently Embedded Initiators.

Herein, we describe a simple and robust approach to repeatedly modify surfaces with polymer brushes through surface-initiated atomic transfer radical polymerization (SI-ATRP), based on an initiator-embedded polystyrene sheet that does not rely on specific surface chemistries for initiator immobilization. The surface-grafted polymer brushes can be wiped away to expose fresh underlying initiator that re-initiates polymerization. This strategy provides a facile route for modification of molded or embossed surfaces, with possible applications in the preparation of fluidic devices and polymer-embedded circuits.

A surface-grafted thermoresponsive hydrogel in which the surface structure dominates the bulk properties

A surface-grafted hydrogel was successfully synthesized by immobilization of the ATRP initiator at the surface region of the gel and the subsequent ARGET ATRP step. This is the first example of a bulk hydrogel with a dense surface-localized layer of a grafted polymer and "active" permeation control of the gel.

Early mobilisation following mini-open rotator cuff repair

This study compared the clinical outcomes following mini-open rotator cuff repair (MORCR) between early mobilisation and usual care, involving initial immobilisation. In total, 189 patients with radiologically-confirmed full-thickness rotator cuff tears underwent MORCR and were randomised to either early mobilisation (n = 97) or standard rehabilitation (n = 92) groups. Patients were assessed at six weeks and three, six, 12 and 24 months post-operatively. Six-week range of movement comparisons demonstrated significantly increased abduction (p = 0.002) and scapular plane elevation (p = 0.006) in the early mobilisation group, an effect which was not detectable at three months (p > 0.51) or afterwards. At 24 months post-operatively, patients who performed pain-free, early active mobilisation for activities of daily living showed no difference in clinical outcomes from patients immobilised for six weeks following MORCR. We suggest that the choice of rehabilitation regime following MORCR may be left to the discretion of the patient and the treating surgeon.

External immobilization of index finger collateral ligament injuries using an improvised frame

Background: Proximal interphalangeal joint (PIPJ) dislocation is a common injury. Current management of instability after closed reduction is repair of the torn ligament followed by immobilization. Important sequelsafter prolonged immobilization include stiffness. On the other hand, early motion exercise may cause rerupture. Buddy taping has been used to partially stabilize the injured finger which also allows early gentle motion.However, this technique cannot be applied to collateral ligament injury of a border finger such as the radial collateral ligament of the index or ulnar collateral ligament of the little finger. Objectives: To describe functional outcomes after application of a frame improvised from a standard disposable syringe in cases of index radial collateral ligament injury. Methods: We constructed adjustable, customized, mobile frames improvised from standard disposable syringe barrels for stabilizing collateral ligaments of the PIPJ to improve motion and protect the repaired ligament. Twopatients with radial collateral ligament injury of the index finger were treated with the improvised frame for 4 weeks after an initial 3-week immobilization with Kirschner wire and a static splint. Results: The average range of motion of PIPJ after treatment was 0-105 with good radioulnar stability. The lifetime of the improvised frame is approximately 8 days, but it can be replaced easily and inexpensively inmost medical facilities. Conclusions: We introduce an improvised which we call a Sriracha frame, as a novel, inexpensive, easyto produce, and effective device that yields good, early joint motion and stability. Keywords: External immobilization, index finger, proximal interphalangeal joint

Marrying mussel inspired chemistry with SET‐LRP: A novel strategy for surface functionalization of carbon nanotubes

ABSTRACTSurface functionalization of carbon nanotubes (CNTs) with a thermo responsive polymer was achieved via combination of mussel inspired chemistry and surface initiated single electron transfer living radical polymerization (SET‐LRP). In this procedure, CNTs were first coated with polydopamine (PDA) through self polymerization under a rather mild condition. And then PDA functionalized CNTs bearing with amino and hydroxyl groups were further reacted with bromo isobutyryl bromide. Finally, a thermo responsive polymer poly(N‐isopropylacrylamide) (PNIPAM) was introduced on the CNTs via SET‐LRP. The successful surface modification of CNT‐PDA‐PNIPAM was evidenced by a series of characterization techniques. The resulting CNT‐PDA‐PNIPAM showed significant enhancement of dispersibility in both aqueous and organic solvents. More importantly, these CNT‐polymer nanocomposites showed obvious thermo responsive behavior due to the surface coating CNTs with PNIPAM. As compared with previous methods, this method is not required oxidation of CNTs to introduce funcitonal groups for immobilization of the polymerization initiators. More importantly, this method could also be utilized for fabricating many other polymer nanocomposites because of the strong and universal adhesive of PDA to various materials. It is therefore, the novel strategy via marrying mussel inspired chemistry with SET‐LRP should be a simple, general and effective method for surface functionalization. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1872–1879

Lab in a Tube: Purification, Amplification, and Detection of DNA Using Poly(2‐oxazoline) Multilayers

Fast and easy purification and amplification of DNA are prerequisites for the development of point‐of‐care diagnostics. For this reason covalent coatings of amine containing poly(2‐oxazoline)s (POx) on glass and poly(propylene) surfaces are prepared, to reversibly bind genetic material directly from biological samples. The polymer is deposited in a layer‐by‐layer process, whereas initial immobilization of macromolecules on the surface is accomplished by the use of an epoxy functionalized siloxane monolayer. Alternating treatment with polymer and cross‐linker leads to the construction of amine containing POx multilayers on the substrates. Successful deposition is investigated by confocal laser scanning microscopy (using labeled polymers), contact angle measurements, as well as reflectometric interference spectroscopy. The interaction of these layer systems with DNA regarding binding and temperature dependent release is studied using labeled genetic material. Finally, polymerase chain reaction (PCR) vessels are coated with POx layers on the inside, and used for quantitative real‐time PCR (qPCR) experiments. It is possible to bind genetic material directly from cell lysates to perform qPCR assays from surface adsorbed DNA within the same tube including amplification, as well as detection. The presented system displays an easy to use device for a point of care diagnostic.

Conservative treatment of mallet finger: A systematic review

PurposeTo determine if there is a superior orthosis and wearing regimen for the conservative treatment of mallet finger injuries. The secondary purpose is to examine the current evidence to evaluate if a night orthosis is necessary following the initial immobilization phase. MethodsA comprehensive literature search was conducted using the search terms mallet finger, splint, orthosis, and conservative treatment. ResultsFour randomized controlled trials (RCTs) were included in the systematic review. In all 4 RCTs mallet fingers were immobilized continuously for 6 weeks in acute injuries and 8 weeks for chronic injuries. ConclusionsTwo of the three studies found a large effect size for orthotic intervention ranging from 2.17 to 12.12. Increased edema and age and decreased patient adherence seem to negatively influence DIP extension gains. Recommended immobilization duration is between 6 to 8 weeks and with additional weeks of immobilization in cases of persistent lags. Level of evidence1a

Impact of the addition of different plant residues on nitrogen mineralization–immobilization turnover and carbon content of a soil incubated under laboratory conditions

Abstract. Application of plant residues as soil amendment may represent a valuable recycling strategy that affects carbon (C) and nitrogen (N) cycling in soil–plant systems. The amount and rate of nutrient release from plant residues depend on their quality characteristics and biochemical composition. A laboratory incubation experiment was conducted for 120 days under controlled conditions (25 °C and 58% water-filled pore space) to quantify initial biochemical composition and N mineralization of leguminous and non-leguminous plant residues, i.e., the roots, shoots and leaves of Glycine max, Trifolium repens, Zea mays, Populus euramericana, Robinia pseudoacacia and Elaeagnus umbellata, incorporated into the soil at the rate of 200 mg residue N kg−1 soil. The diverse plant residues showed a wide variation in total N, C, lignin, polyphenols and C / N ratio with higher polyphenol content in the leaves and higher lignin content in the roots. The shoot of Glycine max and the shoot and root of Trifolium repens displayed continuous mineralization by releasing a maximum of 109.8, 74.8 and 72.5 mg N kg−1 and representing a 55, 37 and 36% recovery of N that had been released from these added resources. The roots of Glycine max and Zea mays and the shoot of Zea mays showed continuous negative values throughout the incubation. After an initial immobilization, leaves of Populus euramericana, Robinia pseudoacacia and Elaeagnus umbellata exhibited net mineralization by releasing a maximum of 31.8, 63.1 and 65.1 mg N kg−1, respectively, and representing a 16, 32 and 33% N recovery, respectively. Nitrogen mineralization from all the treatments was positively correlated with the initial residue N contents (r = 0.89; p &amp;amp;leq; 0.01) and negatively correlated with lignin content (r = −0.84; p ≤ 0.01), C / N ratio (r = −0.69; p ≤ 0.05), lignin / N ratio (r = −0.68; p ≤ 0.05), polyphenol / N ratio (r = −0.73; p ≤ 0.05) and (lignin + polyphenol) : N ratio (r = −0.70; p ≤ 0.05) indicating a significant role of residue chemical composition and quality in regulating N transformations and cycling in soil. The present study indicates that incorporation of plant residues strongly modifies the mineralization–immobilization turnover (MIT) of soil that can be taken into account to develop synchronization between net N mineralization and crop demand in order to maximize N delivery and minimize N losses.

One-Step Immobilization of Initiators for Surface-Initiated Ring Opening Polymerization and Atom Transfer Radical Polymerization by Poly(norepinephrine) Coating.

We report a facile method for surface-initiated ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP) via a poly(norepinephrine) coating. Solid substrates were modified by poly(norepinephrine) under alkaline conditions, with concurrent co-adsorption of an ATRP initiator. The poly(norepinephrine) layer acted as a ROP initiator due to the presence of hydroxyl groups in its side chain, resulting in a surface that was able to initiate ATRP and ROP simultaneously. ε-Caprolactone (ε-CL) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) were grafted onto the surface via ROP and ATRP, respectively, and the polymers subsequently grown from the surfaces were characterized in detail using Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), contact angle goniometry, and atomic force microscopy (AFM).

Polymer grafts on zirconia particles and their application as supports of hybrid catalyst

A facile and efficient strategy for the preparation of polymer grafts on zirconia particles is developed by means of self-initiated photografting and photopolymerization. The UV-induced grafting polymerization is applicable to a variety of polymerizable monomers, allowing the direct formation of homogeneous and stable polymer coatings on zirconia particles without any initiator immobilization. The as-prepared polymer grafts are proved to be efficient supports for polyoxometalates as H3PW12O40 can be uniformly and stably immobilized on a poly(4-vinylpyridine) layer through electrostatic interaction. The resulting hybrid catalyst system, associated with high catalytic activity for a series of oxidation reactions such as amines, alkenes, alcohols and sulfides, represents a novel and efficient system with a high catalyst loading capacity and stability upon reuse in further cycles. © 2014 Society of Chemical Industry

Prolonged chemical restraint of walrus (&lt;i&gt;Odobenus rosmarus&lt;/i&gt;) with etorphine supplemented with medetomidine

Physiological studies involving the use of isotopic water required chemical restraint of free-ranging walruses (Odobenus rosmarus) for several hours. In August 2000, six male walrus (total body mass: 1050–1550 kg) were immobilized in East Greenland by remote delivery of 8.0–9.8 mg of etorphine and subsequently restrained for up to 6.75 h by administration of medetomidine. The effects of etorphine were reversed with 10–24 mg diprenorphine. After termination of the etorphine-induced apnoea, lasting an average of 15.8 min (SD = 9.7, range = 9.5–35.2 min, n = 6), the animals were initially given 10–20 mg medetomidine intramuscularly. The initial dose was further augmented by 5 mg at intervals of 5 min. In two cases, when medetomidine was administered through a catheter inserted in the extradural vein, the animal became instantly apnoeic and regained respiratory function only after intravenous injection of the prescribed dose of the antagonist atipamezole and of the respiratory stimulant doxapram. After an average of 3.5 hours of immobilisation, rectal temperature began to increase and it is conceivable that this is the factor that will ultimately limit the duration of immobilisation. The animals became conscious and fully mobile shortly after an intravenous injection of a dose of atipamezole approximately twice the mass of the total dose of medetomidine given during the procedure followed by 400 mg of doxapram. It is concluded that medetomidine appears to be a suitable drug for chemical restraint of walruses for time-consuming procedures following initial immobilisation by etorphine. With animals of total body mass around 1,000–1,500 kg, the drug should be given intramuscularly in 10–20 mg increments (total mass 10–60 mg) until the breathing rate falls to approximately 1 min-1. At this level, breathing is maintained and animals do not respond to touch or injection.

Cyanuric chloride functionalized silica nanoparticles for covalent immobilization of lipase

AbstractBACKGROUNDIn this work, fumed nano‐silica (FNS) was chemically modified to amino (AFNS) and subsequently to cyanuric chloride (CCAFNS) modified silica and tested for the immobilization of lipase from Candida rugosa (CRL). The effects of the initial enzyme concentration, immobilization time and buffer ionic strength on immobilization were investigated in order to optimize utilization of the support and determine the mechanism of immobilization. The most active preparations were used to examine thermal and operational stability.RESULTSThe amount of immobilized enzyme increased with increasing enzyme concentration, achieving loadings of 121.3, 104.8 and 61.2 mg per g of FNS, CCAFNS and AFNS, respectively. Lipase immobilized on CCAFNS carrier in 0.1 mol L−1 buffer expressed the highest lipolytic activity (1320 IU g−1 support), while more stable preparations were obtained in 1 mol L−1 buffer.CONCLUSIONSuccessful modification of silica was confirmed with Fourier transform infrared spectroscopy and thermogravimetric analysis. Activity results showed that, depending on the support, immobilization was governed by different interactions. On FNS and AFNS immobilization was exclusively by adsorption, while on CCAFNS after the initial adsorption lipase molecules reoriented and amino groups of the enzyme formed a covalent bond with the chlorine atom of the modified carrier. Improved thermal and operational stability of lipase immobilized on CCAFNS in 1 mol L−1 buffer led to the conclusion that electrostatic interactions have a great role in the immobilization. © 2014 Society of Chemical Industry

Middle third clavicular fractures: to fix or not to fix?

Clavicular fractures are common injuries with the incidence quoted between 29 and 198 per 10 000 population per year.1 They are classified into three types:- Type 1: Middle third Type 2: Lateral third (distal to coraco-clavicular ligament) Type 3: Medial third The majority of fractures (> 70%) are type 1. Traditionally these fractures have been treated conservatively with initial immobilisation in a broad arm sling, collar and cuff, or figure of eight strapping. The results of conservative treatment were generally felt to be satisfactory. Nordqvist et al2 in Malmo reviewed 225 mid clavicular fractures at an average of 17 years from injury. The great majority (185/82%) were symptom free. Thirty-nine (17%) had moderate pain and one patient was classified as poor. Fifty-three of the patients had a malunion and seven had nonunions. Forty of the patients with malunited fractures and three with nonunion were rated as good. Fagg1 reviewed the available literature and found an incidence of nonunion of 7% in displaced mid shaft fractures at that time. Thormodsgard et al3 looked at patient satisfaction after non-operative management of clavicular fractures using the Disabilities of the Arm, Shoulder and Hand (DASH) classification. They looked particularly at clavicular shortening and found that patients with shortening of over 2 cm had the highest DASH scores indicating disability and dissatisfaction with their outcome after the injury. They looked at all types of clavicular fracture but found that DASH scores were higher in type 1 fractures. They concluded, “patients with midshaft clavicle fractures with shortening of greater than 2 cm may be good candidates for operative repair.” Murray et al4 assessed the significant risk factors for nonunion in 941 conservatively treated mid shaft clavicular fractures in adults. One hundred and twenty-five (13.3%) had clinical and radiological evidence of nonunion. …

Adhesion and friction properties of fluoropolymer brushes: on the tribological inertness of fluorine.

The effects of fluorination on the adhesion and friction properties of covalently bound poly(fluoroalkyl methacrylate) polymer brushes (thickness ∼80 nm) were systematically investigated. Si(111) surfaces were functionalized with a covalently bound initiator via a thiol-yne click reaction to have a high surface coverage for initiator immobilization. Surface-initiated atom-transfer radical polymerization (SI-ATRP) was employed for the synthesis of four different fluoropolymer brushes (SPFx, where x = 0, 3, 7, or 17 F atoms per monomer), based on fluoroalkyl methacrylates. All polymer brushes were characterized with static contact angle measurements, X-ray photoelectron spectroscopy (XPS), and infrared absorption reflection spectroscopy (IRRAS). The polymer brushes exhibited an excellent hydrophobicity, with static water contact angles of up to 121° depending on the number of fluorine atoms per side chain in fluoroalkyl methacrylate. The degree of swelling was precisely studied by using ellipsometry in different solvents such as acetone, hexadecane, hexafluoroisopropanol, nonafluorobutyl methyl ether, and Fluorinert FC-40. The polymer brushes have shown nanoscale swelling behavior in all solvents except hexadecane. The grafting density decreased upon increasing fluorine content in polymer brushes from 0.65 chains/nm(2) (SPF0) to 0.10 chains/nm(2) (SPF17) as observed in Fluorinert FC-40 as a good solvent. Adhesion and friction force measurements were conducted with silica colloidal probe atomic force microscopy (CP-AFM) under ambient, dry (argon), and lubricating fluid conditions. SPF17 showed the lowest coefficient of friction 0.005 under ambient condition (RH = 44 ± 2%) and a further decrease with 50% under fluidic conditions. These polymer brushes also showed adhesion forces as low as 6.9 nN under ambient conditions, which further went down to 0.003 nN under fluidic conditions (Fluorinert FC-40 and hexadecane) at 10 nN force.

Utah Ski Patrol: Assessing Training Types and Resources

Skiers and snowboarders incur a variety of injuries and medical emergencies each year at ski resorts. The ski patrol is primarily responsible for initial triage, assessment and stabilization of these problems. The purpose of this study was to subjectively evaluate the type of training, resources, and equipment available to local ski patrols within Utah. Ski patrol directors at ski resorts in Utah were asked to complete a voluntary computerized survey. Of the 14 ski areas in Utah, ski patrol directors representing 8 resorts responded. The majority of patrols in Utah use Outdoor Emergency Care (OEC) as their primary education and certification source. Most programs also include site-specific training in addition to basic certification. All responding resorts had basic first responder equipment, including splinting devices, basic airway management, and hemorrhage control. Six of 8 responding resorts had affiliated clinics, and all had access to aeromedical transport. All of the responding ski patrol directors believed the current training level was adequate. Utah area ski patrollers frequently see trauma-related injuries and have the resources to assess and provide initial immobilization techniques. Many resorts have affiliated clinics with advanced providers, and all have access to aeromedical support to rapidly transfer patients to trauma centers. Medical directors may be of use for training as well as developing extended scope of practice protocols for advanced airway use or medication administration. Patrols may benefit from additional resort-specific training that addresses other frequently seen injuries or illnesses.