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Antarctic krill is a potential and attractive resource for consumption. However, most Antarctic krill meat is used to produce primary products with low commercial value, with few highly processed products. This study aimed to evaluate and improve the gelling properties of Antarctic krill surimi, with Pacific white shrimp surimi as control. Compared with Pacific white shrimp surimi, the lower β-sheet content and protein aggregation degree had a severe impact on the formation of the gel network of Antarctic krill surimi, which resulted in weaker breaking force, gel strength, and viscoelasticity (p < 0.05). Moreover, water retention capacity and molecular forces had a positive effect on the stability of the gel matrix of shrimp surimi. Thus, the high α-helix/β-sheet ratio, weak intermolecular interactions, and low level of protein network cross-linkage were the main reasons for the poor quality of Antarctic krill surimi. On this basis, the effects of six polysaccharides on the texture properties of Antarctic krill surimi were studied. Chitosan, konjac glucomannan, sodium carboxyl methyl cellulose, and waxy maize starch resulted in no significant improvement in the texture properties of Antarctic krill surimi (p > 0.05). However, the addition of ι-carrageenan (2%) or κ-carrageenan (1~2%) is an effective way to improve the texture properties of Antarctic krill surimi (p < 0.05). These findings will contribute to the development of reconstituted Antarctic krill surimi products with high nutritional quality and the promotion of deep-processing products of Antarctic krill meat.

Introduction keratoconus is a common disease in the general population, with prevalence ranging up to 200 per 100 000 with a reported increase in Saudi Arabia. Collagen Cross-Linkage is now an established treatment in isolation and in conjunction with other modalities for managing keratoconus. Our aim is to evaluate using a cohort study the impact of the treatment over a course of 18 months. Methods To evaluate the impact of 18 months after collagen cross-linkage treatment and its determinants in eyes with keratoconus in Western Saudi Arabia. A one-armed prospective cohort study design on 45 patients with Stage I, II, III and IV keratoconus who were treated by Collagen Cross-Linkage modality was developed at our institute between 2018 and 2019 to establish the success rate of corneal ectasia stabilization of the disease. Results Demographic data and grades of keratoconus (Amsler - Krumiech classification) at presentation were correlated to changes in corneal parameters 18 months after CXL compared to that at presentation. Stage I, II, III and IV keratoconus were 13, 14, 2 and 16 eyes respectively. The study showed that the K max significantly declined (P = 0.05) while spherical equivalent refractive status changed from median −1.5D to −2.27D (P = 0.002). Meanwhile, Central corneal thickness significantly reduced (P = 0.001). Conclusion CXL can prove to be efficient in the treatment of Keratoconus and more studies should study ways to improve and implement this treatment plan to such patients., Highlights • Keratoconus prevalence has been increasing in Saudi Arabia and the world. • Studying treatment procedures of the disease is important to determine the best course of action. • Collagen Cross-Linkage Treatment is a treatment option that showed variation of success rate in the literature.

Disulfide bonds are a significant motif in life and drug-delivery systems. In particular, steric hindrance and stereoscopic disulfide linkers are closely associated with the stability of antibody–drug conjugates, which affects the potency, selectivity, and pharmacokinetics of drugs. However, limited availability and diversity of tertiary thiols impede the construction of steric and stereoscopic disulfides for cross-linkage in biochemistry and pharmaceuticals. Through modulating the mask effect of disulfurating reagents, we develop a facile and robust strategy for construction of diverse steric and stereoscopic disulfides via N-dithiophthalimides. The practical cross-linkage of biomolecules including amino acids, saccharides, and nucleosides with different drugs and fluorescent molecules is successfully established through hindered disulfide linkers., A series of steric and stereoscopic disulfides are constructed with N-dithiophthalimides, enabling the cross-linkage of biomolecules, drugs and fluorescent molecules.

Purpose: To evaluate the accuracy of the Corvis Biomechanical Index (CBI) in screening of patients with Keratoconus. Study Design: Cross sectional study. Place and Duration of Study: Amanat Eye Hospital Peshawar from July 2018 to June 2019. Material and Methods: One thousand eyes were included in this study. Patients who came for keratorefractive laser procedure or collagen cross linkage were included in the study by convenient sampling technique. Six hundred and eleven patients had early Keratoconus and 389 were normal controls. Control group included those individuals who had visual acuity of 6/6 with no clinical feature of Keratoconus and normal TBI. All individuals included in the study underwent a thorough ocular examination, CBI and TBI tests. SPSS version 23 was used for statistical analysis of collected data. Results: The mean CBI value was 0.3186 ± 0.407 standard deviation (SD), the standard error (SE) of the mean was 0.0129 with a 95% confidence interval (CI) of 0.293 to 0.343. The minimum CBI value was 0.00 and the maximum value was 1.00. The mean Tomographic Biomechanical Index (TBI) value was 0.465 ± 0.392 SD, SE was 0.124 with a 95% CI of 0.222 to 0.708. The range of TBI values was 0.00 to 1.00. For CBI, sensitivity was 58.2%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 61.2%. Conclusion: Although CBI is accurate in terms of specificity and sensitivity, the result should be interpreted in combination with clinical data and other topographic and tomographic parameters.

We studied the effect of the extremely high cross-linkage degree on the isotope separation in cation exchange. The cation exchange resin with 90% degree of cross-linkage was synthesized by suspension polymerization. The lithium isotope separation was obtained by the displacement chromatography using this synthesized cation exchange resin. From the results of our previous research, the isotope separation coefficient increases with the degree of cross-linkage. However, it was found from the present work that the isotope separation is saturated in the case of very high degree of cross-linkage.

The lithium isotope separation by the displacement chromatography using cation exchange resin has been studied. The cross-linkage effect of cation exchange resin on lithium isotope enrichment was confirmed by using the commercial cation exchange resin in our previous paper. In the present work, we synthesized the cation exchange resin with 50% cross-linkage, which is higher cross-linkage ratio than the commercial cation exchange resin, and the cation exchange isotope separation experiment using synthesized resin was carried out. As a result, we obtained the isotope separation coefficient of 6.6×10−3. This isotope separation coefficient is the highest one among results obtained by the cation exchange isotope separation methods.

Aim To evaluate the role and efficacy of collagen cross-linkage with riboflavin (C3R) in cases of progressive keratoconus. Study design Prospective, nonrandomized, single-center clinical study. Materials and methods The C3R was done in 32 eyes of 21 patients with at least 6 months of documented progression. Outcome of the procedure was measured by means of uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), corneal topography with Orbscan changes in posterior best fit sphere (PBFS), ratio of anterior and posterior best fit sphere (ABFS/PBFS), astigmatic changes in central 3- and 5-mm zone, central endothelial count postcorneal C3R. Results Thirty-two eyes with a follow-up of 6 months were analyzed. The mean age was 19.8 years. The preoperative values on the day of treatment were compared with postoperative values after the 6-month examination. The improvement in UCVA and BSCVA was statistically significant (p = 0.02 and 0.01 respectively). The change in power for PBFS was not statistically significant (p = —0.08). There was no significant difference in corneal endothelial counts pre- and post-C3R (p = 0.058). Mean value pre-C3R for ratio of ABFS/PBFS was 1.25 ± 3.7 and post-C3R was 1.22 ± 1.8 (p = 0.00). Mean value of astigmatism in 3-mm zone pre- and post-C3R was —4.3 ± 0.98 and —3.9 ± 0.66(p = 0.046) respectively. Mean value pre-C3R for astigmatism in 5-mm zone was —4.9 ± 1.91 and post-C3R was —4.0 ± 0.82 (p = 0.02). Conclusion The results show a stabilization and improvement in keratoconus after C3R in Indian eyes. How to cite this article Guleria P, Sharma V. To evaluate the Role and Efficacy of Collagen Cross-linkage with Ultraviolet Therapy following Riboflavin Drops with Orbscan in Cases of Progressive Keratoconus. Int J Kerat Ect Cor Dis 2017;6(2):67-72.

Are there many things simpler than a rope? I can remember at the beginning of my career when most clinicians viewed the anterior cruciate ligament as a static check rein that contributed to the mechanical four-bar cross linkage roll/glide mechanism of the knee joint. It was purely a mechanical view of the ligament, which was viewed basically as a ‘rope’ that sometimes broke in the knee. We woefully underestimated its neurologic, biological and psychological impact when injured. The situation was far from as simple as we perceived it. As orthopaedists, we are not alone in our failure to appreciate the complexity of the human body and the power of the poorly understood mind–body interaction.

Recently, graphene oxide (GO) membranes are highly attractive for their exceptional separation performance. However, their sieving characteristics limit GO membranes for some important applications where organics are preferred or organic solvents are employed. In this work, a novel cross-linked graphene (CG) membrane is fabricated through compressing and then reducing a cross-linked GO aerogel. It achieved high-performance of organics separation with high flux (225 L m−2 h−1) and purity (>99.98%) even in a cross-flow separation model, where water was intercepted. Deep insight revealed that both the converted surface wettability and the remaining channels in the CG membrane were crucial for the high-performance of organics separation. Beyond that, this CG membrane offers many advantages, such as facile preparation, self-supporting, structural stability and adaptation in harsh acidic/basic/high-temperature conditions, demonstrating its great potential for practical applications.

Purpose Presenting the course of visually disabling corneal infiltration post uneventful collagen cross-linking (CXL) in a 23 years old male with bilateral keratoconus. Methods A 23 years old male with bilateral keratoconus underwent cross-linking of left eye with indigenous 0.1% riboflavin dye and 370 nm ultraviolet A irradiation. This patient had an uneventful successful cross-linking performed in right eye 6 months prior with good recovery of vision to LogMAR (6/9 Snellen). Results Patient developed diminution of vision, along with redness of eye, photophobia and watering on 3rd day after uneventful cross-linkage. Examination revealed very poor vision; diffuse corneal clouding with multiple superficial stromal infiltrates and incomplete corneal epithelization. A provisional diagnosis of infective keratitis was made, in situ bandage contact lens (BCL) removed and subjected to culture. Intensive fortified topical antibiotics were initiated and steroids withheld. After complete corneal re-epithelization on 6th day, the infiltrations did not decrease in either intensity or number. Response to antibiotics being inadequate, an immune etiology was suspected and full strength topical steroids reinstituted which resulted in slow resolution of infiltration over a 10 weeks period. Last follow-up at 9 months post-CXL, revealed a diffuse stromal haze with unaided visual acuity of LogMAR 0.8 6/36 and best-corrected visual acuity (BCVA) of 0.3 (6/12) with use of a rigid gas permeable lens. Conclusion Sterile infiltration post-CXL requiring intense topical steroids is a rare complication of CXL and needs to be differentiated from infective keratitis. How to cite this article Bhattacharyya M, Singh K, Mutreja A, Dangda S, Arora R. Diffuse Sterile Corneal Infiltration: An Unusual Complication Post Collagen Cross-linkage. Int J Kerat Ect Cor Dis 2015;4(3):115-119.

Objective To compare post-operative pain relieving effect of topical diclofenac 0.1% versus ketorolac 0.5% in Corneal Collagen Cross Linking (CXL) for patients diagnosed with keratoconus. Methods This randomized controlled trial was carried out for six months from October 2016 to March 2017. We included young patients having keratoconus with k-readings greater than 47D and central corneal thickness more than 400 microns. All the patients received single dose one drop of topical diclofenac 0.1% to (Group-A) and ketorolac 0.5% to (Group-B) 30 minutes in advance of the corneal collagen cross linking (CXL) procedure. The CXL was performed with topical 0.1% riboflavin eye drops in 20% dextran as a photo sensitizer. After 36 hours of the CXL procedure, the postoperative intensity of pain was assessed verbally by patients with the help of visual analog scale (VAS) numbers from zero to five where 0 designated no pain & 5 symbolized worst pain. Results The study comprised sixty eyes of forty one patients. Out of total 16 were male while 25 female patients. The mean age of the patients was 24.27 ± 2.93 years (range 20 to 29 years). In the conclusive analysis, diclofenac 0.1% was used on 30 patients in Group-A and ketorolac 0.5% on 30 subjects in Group-B. Pain relieving scores in Group-A (diclofenac 0.1%) was 2.57 ± 0.67 while in Group-B (ketorolac 0.4% treated arm) was 3.20 ± 0.61. Conclusion Topical diclofenac 0.1% is statistically comparable to topical ketorolac 0.5% in precluding severity of pain after corneal collagen cross linkage operation.

Diagnosis of osteomyelitis presents a formidable challenge. Lack of pathognomonic clinical sign(s) and diagnostic tests that can diagnose osteomyelitis at an early stage contribute to this difficulty. If the diagnosis is not made early, the disease becomes very difficult to eradicate and can lead to limb threatening and potentially life-threatening complications. Staphylococcus aureus is the most common organism causing osteomyelitis. Raman Spectroscopy provides information about molecular vibration that could potentially be harnessed as a spectral signature for cellular changes in specific pathologic conditions. In this study we describe a technique using Raman spectroscopy that could potentially be used to diagnose staphylococcal osteomyelitis. Human bone samples were co-cultured with Staphylococcus aureus (S. aureus) and the effects of bacterial growth on bone quality were then monitored using Raman spectroscopy. A major drop in the bone mineral quality and crystallinity was observed in the infected bones compared to the controls. S. aureus infection was also found to alter the collagen cross-linking. Our study shows that specific spectral signatures are present for the cause as well as the effect of staphylococcal osteomyelitis, opening the possibility of developing a useful diagnostic modality for early and rapid diagnosis of this condition.

Soluble myosin and insoluble protein (i. e., soluble only in 5 % sodium dodecyl sulfate) were obtained from fresh and processed Sacramento blackfish and analyzed for the existence of possible cross-links. Free sulfhydryl groups decreased somewhat in freezing and more in frozen storage. None were present after dehydration or cooking nor in any insoluble fractions, so that presumably these were oxidized in the formation of cross-links. Ester bonds were much more numerous in insoluble protein than in soluble myosin, but their relative content was not clearly related to processing. Aldehyde groups decreased in myosin after cooking and dehydration, and were absent from insoluble protein. The presumptive Schiff base content was somewhat greater in soluble protein than in myosin and appeared to increase upon freezing and dehydration.

PVA hydrogel has been used in the field of cartilage replacement in recent year. In order to improve the water-keeping ability of PVA gel and mechanical property, PVP was introduced into PVA and crosslinked by adding ammonium persulfate to form a composite gel. The crosslinkage of the gel was identified, and the effect of PVP and ammonium persulfate amount on the composite gel was studied. The crosslinkage, the degree of swelling and the compress stress of the composite gels have been tested. UV analysis was used to investigate the release of PVP from the composite gels. The dried composite gels were put into water to investigate the degree and velocity of the rehydration of different composite gels.

Dear Editor, There are many methods for achieving primary haemostasis in the tonsillar fossa after tonsillectomy. A common method is that of ligating the bleeding vessel using Negus artery forceps and Negus ligature carrier. In this method after the ligature is tied around the Negus artery forceps the free ends of the ligature are wrapped around the fingers of both the hands. The knot is then pushed down into the tonsillar fossa using a Negus ligature carrier. This requires considerable practice and juggling movements of the hands since both the hands are occupied in holding the free ends of the ligature. To overcome the problem of holding the free ends of the ligature, a ligature holding forceps has been devised and used successfully at our hospital. The forceps consists of two straight artery forceps joined together by a cross linkage, one set of finger loops of the forceps are welded together to provide additional stability (Fig-1). The free ends of the knot which is tied around the Negus artery forceps is held by this ligature forceps instead of the fingers of both hands. The ligature forceps is held in one's hand while the other hand is free to hold the Negus ligature carrier and push the knot down into the tonsillar fossa for achieving haemostasis. Fig. 1 Mehtas ligature forceps for tonsillectomy

Mapillary is a VGI platform which allows users to contribute crowdsourced street level photographs from all over the world. Due to unique information that can be extracted from street level photographs but not from aerial or satellite imagery, such as the content of road signs, users of other VGI Web 2.0 applications start to utilize Mapillary for collecting and editing data. This study assesses to which extent OpenStreetMap (OSM) feature edits use Mapillary data, based on tag information of added or edited features and changesets. It analyzes how spatial contribution patterns of individual users vary between OSM and Mapillary. A better understanding of cross-linkage patterns between different VGI platforms is important for data quality assessment, since cross-linkage can lead to better quality control of involved data sources.

To evaluate the embolic effect and degradability of gelatin microspheres (GMS) using various degrees of cross-linkage and particle sizes in rabbit renal artery embolization. Four types of GMS were used, as follows: 2 types of cross-linkage and 2 types of particle size. Twenty-four rabbits (6 in each group) were used for the renal artery embolization. Renal angiography was performed before and after embolization of right renal artery. Follow-up renal angiography was performed 2 days (n = 2), 5 days (n = 2), and 15 days (n = 2) after embolization in each group, and then kidneys were removed for histopathological evaluation. Vascular areas of the angiography were measured by Image J software, and the reperfusion rate was calculated. In renal specimens, residual GMS were checked and the degree of degradation was classified according to a 4-point scale. The mean amounts of large- and small-particle-size GMS injected were 15.0 and 34.3 mg, respectively. Tissue necrosis was confirmed in each group; however, no difference was observed among groups. Renal reperfusion was observed more with small GMS than with large GMS. Renal reperfusion was also observed more with low cross-linked GMS than with high cross-linked GMS. In histopathological specimens, large GMS were confirmed in lobar artery, and small GMS were confirmed in lobular artery. Low cross-linked GMS completely degraded 15 days after embolization. In contrast, high cross-linked GMS were persistent 15 days after embolization. Degree of cross-linkage and particle size affected degradability and reperfusion.

Individuals with keratoconus form a significant proportion of patients for a practitioner specialising in corneal diseases. Yet it is a disease where the pathogenesis is poorly understood, and until recently, there has been no treatment apart from transplantation that could be offered that was curative or even capable of slowing the progression of the disease. Collagen cross-linking treatment using riboflavin and UV light has been developed to address this need, and the initial results are promising. The purpose of this review is to critically evaluate this treatment in light of the scientific basis for cross-linking, to highlight the strengths and limitations of the evidence in terms of efficacy and long-term safety, and finally to identify areas for future research in this area with a significant potential to change the way we treat our keratoconus patients. In addition, we hope that our unbiased review for the first time would bring together, in a concise fashion, scientific information for a practitioner contemplating on offering this treatment and to help inform their patients of its potential risks and benefits.

First-principles calculations were utilized to study the formation mechanisms and structural features of fullerene-like carbon nitride (FL CNx). Cohesive energy comparisons reveal the energy cost for different defects arising from substitution of C for N as a function of the nitrogen concentration. In FL CNx, combinations of pentagons and heptagons compete in causing graphene sheet curvature during the addition of CN-precursors and single species. Also, cross-linkage between graphene layers in FL CNx can be explained by the bond rotation due to incorporated N atoms. The computational results agree with recent experimental observations from the growth of FL CNx thin films.

Hydroxyapatite(HAp)/collagen nanocomposites were prepared by a coprecipitation method controlling the degree of cross-linkage between collagen molecules using glutaraldehyde. The precipitates filtered were dried in a freeze drier or naturally dried in the air at 25 °C. The naturally dried cakes had open channels of 5–15 μm in diameters, which were three-dimensionally and regularly developed over the whole samples, and showed a pretty good mechanical strength. The channels that were formed at spaces among the HAp/collagen particles, cross-linked one another, which had been filled up with water before its evaporation. The ordering state of the open channels depended on the degree of cross-linkage with glutaraldehyde; the optimal self-organized state was found when 30 molecules of glutaraldehyde were added per collagen molecule, though an excess amount of glutaraldehyde suppressed the appearance of the ordered state. From SEM and FT-IR measurements, it was indicated that the self-organization in the HAp/collagen nanocompsites continuously occurred during the drying process together with the removal of water and the increase of the density.

Resorbable filling materials are currently the safest products available. The side effects with this type of material are few compared to the number of patients treated. We can therefore suggest materials that have maximum safety to our patients, particularly in cosmetic indications.

Cross-linked complex between photosynthetic reaction center and horse heart cytochrome c (cyt c ) was prepared for the control of molecular orientation in Langmuir–Blodgett (LB) method. The surface of cyt c is highly hydrophilic whereas that of RC is hydrophobic. A polar distribution of hydrophobicity/hydrophilicity in the complex was realized by the cross-linkage of the different protein molecules. An index was introduced to evaluate the hydrophobicity of the surface of the proteins. The orientation of RCs in an LB film was evaluated by the displacement current. The complex showed a response 1.5 times larger than that of RC.

The pathogenesis of aneurysms formation and rupture is not clearly understood and is undoubtedly a multifactorial event. It is generally accepted that the aneurysm arises from an interaction between structural weakness of arterial wall and hemodynamic factors. Previous studies suggested the possible role of collagenolytic and elastolytic activities in aneurysm development, leading to extracellular matrix alteration. The content of collagen 3-hydroxypiridinium cross-links and elastase and collagenase activities were measured in 12 samples of intracranial aneurysms and in control specimens obtained from temporal superficial arteries and from autoptic samples of Willis Circle. Collagen content is significantly lower in aneurysm than in autoptic control samples (p0.01). The total amount of cross-links is significantly lower in ruptured aneurysms than in unruptured and autoptic controls (p0.01). Collagenase and elastase activities are significantly increased in ruptured cerebral aneurysms versus unruptured aneurysms (p0.01). Linear regression shows that an inverse relationship exists between cross-links content and both elastolytic (p = 0.0032) and collagenolytic (p0.001) activities in aneurysmal samples. Multiple regression shows that collagenase has a more important statistic impact (p = 0.027) than elastase (p = 0.08). The results of the study supports the hypothesis that an imbalance of protease-antiprotease homeostasis with elevated collagenolytic and elastolytic activities may represent the predisposing condition leading to aneurysms rupture through collagen depauperation and reduced cross-linkage of collagen fibres.

Appearance of Edwardsiella tarda were monitored in pond water culturing eel Anguilla japonica in Kagoshima prefecture. E. tarda were isolated at almost all sampling times. Serotype and siderophore production of the E. tarda isolates, which are involved with its pathogenesis, were determined. Out of 370 isolates, 194 isolates (52%) were classified into serotype A and 246 isolates (66%) produced siderophore. Ninety-one percent of the isolates that were classified into serotype A produced siderophore;72%of those that produced siderophore were classified into serotype A. There was no cross linkage between serotype and siderophore production in E. tarda.

In the field of aesthetic medicine there is an increasing demand for safe and effective hyaluronic acid (HA) fillers to counteract the aging process.We designed a study to evaluate the safety and histological biocompatibility of Aliaxin® Global Performance, a cross-linked HA filler and Viscoderm® Skinkò E, a product composed of non-cross-linked HA and a complex including vitamins, antioxidants, amino acids and minerals injected into the skin of guinea pigs. Then, we translated our findings into the clinical setting, administering a combination of these compounds to patients seeking a facial rejuvenation procedure targeting moderate-to-severe wrinkles affecting the nasolabial folds.The animal study showed that the two compounds did not induce any significant inflammatory reactions and increased collagen and elastic fibers in the skin. In the clinical setting, injection of Aliaxin® Global Performance, followed by Viscoderm® Skinkò E, resulted in a higher improvement in nasolabial fold hydration, trans-epidermal water loss and wrinkle aesthetic appearance, if compared with a protocol based on Aliaxin® Global Performance alone.In summary, we show evidence on the safety and mechanism underlying two new HA-based compounds of different cross-linkage and composition, proposing that they can be safely used in combination in patients seeking facial rejuvenation procedures with long-lasting efficacy.

Wear, frictional torque and creep deformity of UHMWPE sockets crosslinked by gamma radiation of 100, 500 and 1000 Mrad in combination with 28 mm alumina heads, were measured using a hip simulator (under constant load 250 kgf with lubrication of saline solution). Hardness and hydrophilic increased and creep deformity decreased as a result of gamma radiation. The initial wear (decrement of the thickness) of the socket with radiation of 0, 100, 500 and 1000 Mrad was, 150 μm, 100 μm, 70 μm and 50 μm, respectively. The time to steady-state wear at 0, 100, 5000 and 1000 Mrad was about 0.15 million, 0.15 million, 0.1 million, and 0.05 million cycles, respectively. The steady-state wear (decrement of the thickness) of the socket without and with radiation was 200 μm/million cycles and less than 20 μm/million cycles, respectively. Rotational torque was under 0.65 Nm in every case. Swing frictional torque at radiation levels of 0, 100, 500 and 1000 MRad were 1.60–2.84 Nm, 3.24–9.02 Nm, 5.23–8.78 Nm, and 2.51–6.79 Nm, respectively.

Gel electrophoresis analysis of CPI-I bisalkylation of a 21-mer duplex containing 5‘-TAA2TTA1-3‘ (the palindromic preferred cross-linking sequence of the (+)-CC-1065 analog Bizelesin) shows same-strand (strand one) alkylation of first A1 and then A2 instead of the anticipated symmetrical A1 alkylation of strands one and two. Two-dimensional NMR analyses (NOESY and COSY) confirm the head-to-tail minor groove orientation of the same-strand-bound drugs. CPI-I contrasts sharply with Bizelesin (two CPI-I units linked tail-to-tail by a ureadiyl “linker”), which symmetrically cross-links this sequence at A1 (strands one and two), but only by first rearranging the duplex structure and consequently removing the duplex distortion stemming from monoadduct formation. CPI-I induces no such major DNA rearrangement prior to or during bisalkylation. Why does CPI-I react with the adenines of only a single strand? Two possible causes for the unexpected strand one A2 alkylation are, first, retardation of strand two A1 site'...

Study of binding of the cationic surfactant molecule-N-dodecylpyridinium chloride (C 12 PyCl)-onto the anionic polyelectrolyte network-poly[2-(acrylamido)-2-methylpropanesulfonic acid] (PAMPS) gel-with different cross-linking densities was made and compared with that with linear PAMPS. The experimental results showed that the presence of cross-linkage significantly enhances the initiation process but strongly suppresses the cooperativity of the binding. The binding process of the surfactant onto the charged network was interpreted in terms of osmotic pressure of the gel which results from the conformational shrinkage caused by the surfactant binding.

It's well known that irreversible cross-linked complexes between proteins, produced by formaldehyde interacting with free amino or amide groups to form Schiff s base, are formed in diabetes and aging patients. To identify such specific modified peptides as biomarkers for clinical diagnose of diabetes and AD, cross-linkage of formaldehyde with human serum albumin (HSA) was analyzed by LC/ESI/MS in this study. Eighteen peptides as important biomarkers were identified and the corresponding possible structures of their cross-linkages were also analyzed. Five of those peptides were modified by the reaction of one molecular proportion of formaldehyde with one molecular proportion of amino group. Reaction of one molecular proportion of formaldehyde with two molecular proportions of amino groups were found in 4 of the 18 peptides. In the rest 9 peptides, the structures of the cross-linkages of formaldehyde with amino groups was more complex. Furthermore, several lysine and arginine residues of those peptides were proved as modification sites in HSA cross-linked with formaldehyde.

FTIR spectroscopy has been used to characterize a bituminous coal from the Pozo Maria Luisa in Asturias (Spain) and to analyze the effects of varying the time (from 0 to 4 days) of oxidation at 270° C. The goal is to obtain information on aromaticity, non aromatic hydrogens and various functional groups.

Colloidal calcium phosphate (CCP)-increased casein micelle dispersion (CMD) was prepared by adding calcium chloride and dipotassium phosphate to CMD adjusting the pH to 6.7. The content of casein aggregates cross-linked by CCP in casein micelles was increased from 49.3 to 68.3% by adding calcium and phosphate to CMD. The amount of serum casein released from casein micelles on cooling decreased with increasing CCP content. Since it is probable that β-casein is only released from β-casein which is not cross-linked by CCP in casein micelles, β-casein in casein micelles was divided into the three types: cross-linked by CCP; not cross-linked and released on cooling; not cross-linked and not released on cooling. When the CCP content was increased to a large extent, β-casein released on cooling decreased from 31.8 to 2.1% of the total β-casein, while β-casein cross-linked by CCP and β-casein which is not cross-linked and not released on cooling were increased from 46.2 to 69.9% and from 22.0 to 28.0% of the tota...

We read with great interest the work of O'Brart and associates regarding the efficacy of riboflavin/ultraviolet-A corneal collagen cross-linkage to halt the progression of keratoconus.1 There has been enough literature published to establish the efficacy of collagen cross-linking, but prospective randomised clinical trials to establish the cause–effect relationship are lacking. Hence the intention to find such association is praiseworthy. It is important to consider the natural course of the disease in any study relating to the efficacy of intervention in modifying the disease course. However, it seems this was not considered in the present study. Also, keratoconus is a bilateral asymmetrical disease with varying rates of progression. Hence, is taking the fellow eye as control for a clinical trial perfect? The mean …

Purpose: To evaluate the outcome of same day topographic-guided photorefractive keratomileusis (PRK) and corneal cross-linkage in patients with subclinical keratoconus. Materials and Methods: A total of 20 patients with subclinical keratoconus were treated with topographic-guided PRK and same day corneal collagen cross-linkage with riboflavin. Inclusion criteria was low grade myopia of up to 3 diopter spherical equivalent, corneal thickness more than 475 microns, maximum keratometry reading K max less than 50 D. Results: Median preoperative spherical equivalent refraction was −2.25 D. At final follow-up visit at 1 year spherical equivalent was statistically significantly reduced to −0.25 D ( P Conclusion: Same day topographic-guided PRK and corneal cross-linkage is a safe treatment offering good vision in subclinical cases of keratoconus.

Relaxation Mossbauer spectra of two57Fe3+-exchanged acrylate cation-exchangers (SGK-7 and SG-1M, USSR) with various cross-linkage concentrations 2.5–16 mol.% were observed in windows of observation up to 250 mm/s. The frequencies of slow (ω≲10 s−1) intramolecular motions (displayed in Mossbauer lineshape) and the values of high frequency (ω≳10 s−1) atomic displacements (reflected in thef’ factor) decrease with the increase of cross-linkage concentration.

Aims Outbreaks of healthcare-associated infection (HCAI) in neonatal units (NNUs) have a significant burden of morbidity and mortality and cause substantial disruption and cost to neonatal networks. The number of NNU HCAI clusters in 2011 in England, their size and causative organisms, were estimated using currently available surveillance tools. Methods Data derived from voluntary laboratory reporting (LabBase 2), national reference laboratories and a Health Protection Agency outbreak reporting tool (HPZone) were searched to identify potential NNU HCAI clusters. The analysis was limited to the most likely causative organisms ( S. aureus , Enterobacter spp., E. coli , Acinetobacter spp., Klebsiella s pp., Pseudomonas spp., Serratia spp.) . Clusters were defined as: (i) any neonatal cluster or outbreak reported in HPZone; (ii) laboratory reports of at least 2 isolates originating from the same hospital and sharing the same VNTR or strain type, with at least one case below the age of 28 days, and with a maximum of 14 days between two cases, and (iii) 2 or more reports of the same infection in neonates in the same hospital in a 14 day period in LabBase. Cross linkage of the 3 data sources was then attempted. Results 116 neonatal clusters including both colonisation and invasive disease were identified, involving at least 666 neonates. 43.4% of the clusters were MRSA, followed by MSSA (26%), E.coli (13%), Enterobacter (12%), and Pseudomonas (10%). There were on average 9.2 neonatal clusters per month (range 0–14). The median number of babies per cluster was 3 (range 2–80). When only bacteraemia samples were considered, E.coli was the most common organism accounting for 57% of clusters. The study likely underestimates the number of clusters due to a lack of standardised reporting. It was not always possible to fully characterise the clusters as formal outbreaks due to data limitations. Conclusion This analysis identified a high number of HCAI clusters in English NNUs. A standardised approach to the definition, reporting, management and surveillance of NNU HCAI outbreaks is required to enable reliable outbreak detection and appropriate action.

Development of colonic diverticulosis is a function of age and declining colonic wall mechanical strength. The latter is partly a consequence of changes in the collagen structure. Collagen from unaffected human colons (n = 20, age range 20-80 years) and those with colonic diverticulosis (n = 5, age range 67-80 years) were obtained at necropsy. The total collagen content was measured as the hydroxyproline content and cross linkage by collagen solubility in weak acid was studied. The colonic total collagen content was constant with age (mean (SD) 15.8 (0.3) mg/100 mg wet weight of tissue). The acid solubility of the collagen, however, increased after the age of 40 years: at over 60 years, colonic diverticulosis was associated with an increased acid solubility ratio compared with values in unaffected colons (15.3 (0.2); compared with 9.2 (0.2), p < 0.001). The cross linking of colonic collagen increases with age. These changes seem to be a factor in the aetiology of colonic diverticulosis.

This study tested the effects of cross-linkage on the fatigue performance of posterior spinal constructs (i.e., AcroMed stainless steel Isola systems). The failure modes encountered during fatigue were also examined. The results of this study confirmed earlier findings that the use of cross-linkage does not significantly affect the stability of posterior constructs during axial loading. Their influence in torsion loading is much more pronounced. During the fatigue tests, posterior stainless steel spinal implants instrumented without cross-linkage reached 1 million cycles at 500- and 750-N loads. When the load was increased to 1,000 N, the number of cycles to failure dropped by two-thirds. These findings demonstrate that the endurance limit was between 750 N and 1,000 N for spinal constructs without cross-linkage, with the limit being closer to 750 N. Devices equipped with one or two cross-linkages reached 1 million cycles at 500 N. The number of cycles to failure dropped dramatically as the load was increased to 750 and 1,000 N. It appears that the endurance limits for spinal devices using cross-linkage should be 500 and 750 N, with the limit closer to the 500-N load. All rod fractures occurred near the junction between the longitudinal and transverse rods. Stress concentration was greatly in the vicinity of that contact point. These results should provide a basis for future improvement in endurance limits of spinal implants equipped with cross-linkage. Higher endurance limits will reduce the toxic effects encountered during fracture modes. The implants will also be better able to withstand the high physiologic loads experienced by obese individuals.