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Laser-induced forward transfer (LIFT) is a rapid laser-patterning technique for high-throughput combinatorial synthesis directly on glass slides. A lack of automation and precision limited LIFT applications to simple proof-of-concept syntheses of fewer than 100 compounds. Here, we report an automated synthesis instrument that combines laser transfer and robotics for parallel synthesis in a microarray format with up to 10000 individual reactions/cm2. An optimized pipeline for amide bond formation is the basis for preparing complex peptide microarrays with thousands of different sequences in high yield with high reproducibility. The resulting peptide arrays are of higher quality than commercial peptide arrays. More than 4800 15-residue peptides resembling the entire Ebola virus proteome on a microarray were synthesized to study the antibody response of an Ebola virus infection survivor. We identified known and unknown epitopes that serve now as a basis for Ebola diagnostic development. The versatility and precision of the synthesizer is demonstrated by in situ synthesis of fluorescent molecules via Schiff base reaction and multi-step patterning of precisely definable amounts of fluorophores. This automated laser transfer synthesis approach opens new avenues for high-throughput chemical synthesis and biological screening.

Automated chemical synthesis has revolutionized synthetic access to biopolymers in terms of simplicity and speed. While automated oligosaccharide synthesis has become faster and more versatile, the parallel synthesis of oligosaccharides is not yet possible. Here, a chemical vapor glycosylation strategy (VaporSPOT) is described that enables the simultaneous synthesis of oligosaccharides on a cellulose membrane solid support. Different linkers allow for flexible and straightforward cleavage, purification, and characterization of the target oligosaccharides. This method is the basis for the development of parallel automated glycan synthesis platforms.

The use of organic materials with reversible redox activity holds enormous potential for next‐generation Li‐ion energy storage devices. Yet, most candidates are not truly sustainable, i.e., not derived from renewable feedstock or made in benign reactions. Here an attempt is reported to resolve this issue by synthesizing an organic cathode material from tannic acid and microporous carbon derived from biomass. All constituents, including the redox‐active material and conductive carbon additive, are made from renewable resources. Using a simple, sustainable fabrication method, a hybrid material is formed. The low cost and ecofriendly material shows outstanding performance with a capacity of 108 mAh g−1 at 0.1 A g−1 and low capacity fading, retaining approximately 80% of the maximum capacity after 90 cycles. With approximately 3.4 V versus Li+/Li, the cells also feature one of the highest reversible redox potentials reported for biomolecular cathodes. Finally, the quinone‐catecholate redox mechanism responsible for the high capacity of tannic acid is confirmed by electrochemical characterization of a model compound similar to tannic acid but without catecholic groups., Tannic acid and sucrose‐derived porous carbon are combined to create a hybrid material using ball milling. The sustainable hybrid material shows exceptional properties as a cathode material for lithium‐ion energy storage devices that combines energy storage using both a redox process, from tannic acid, and electric double‐layer capacitance, from the porous carbon., DFG http://dx.doi.org/10.13039/100004807, German Federal Ministry of Education and Research, BMBF http://dx.doi.org/10.13039/501100002347, Fraunhofer‐Max Planck cooperation project, Max Planck Society http://dx.doi.org/10.13039/501100004189, Max Planck Institute of Colloids and Interfaces, Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Objectives Clinical practice guidelines (CPG) provide evidence-based recommendations for patient care but may not be optimally applied in clinical settings. As a pilot study, we evaluated the impact of a computerized, point-of-care decision support system (CDSS) on guideline knowledge and adherence in our diabetes clinic. Methods iSCREEN, a CDSS, integrated with a province-wide electronic health record, was designed based on the Canadian Diabetes Association 2013 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada. Evaluation data were gathered by retrospective chart review and clinician questionnaire prior to and after implementation of iSCREEN. Records of patients with type 1 diabetes, 14 to 18 years of age, were assessed for appropriate screening for complications and comorbidities. Results To assess guideline adherence, 50 charts were reviewed at 2 time periods (25 before and 25 after launch of iSCREEN). Results revealed improved frequency of appropriate screening for diabetic nephropathy (p=0.03) and retinopathy (p=0.04), accompanied by a decrease in under- and overscreening for these outcomes. To assess guideline knowledge, 58 surveys were collected (31 prior to and 27 after the launch of iSCREEN) from care providers in the field of pediatric diabetes. There was a trend toward improved guideline knowledge in all team members (p=0.06). Conclusions Implementation of a de novo CDSS was associated with improved rates of appropriate screening for diabetes-related complications. A trend toward improvement in health professionals' knowledge of the guidelines was also observed. Evaluation of this point-of-care computerized decision support tool suggests that it may facilitate diabetes care by optimizing complication screening and CPG knowledge, with the potential for broader implementation.

Single glycan–protein interactions are often weak, such that glycan binding partners commonly utilize multiple, spatially defined binding sites to enhance binding avidity and specificity. Current array technologies usually neglect defined multivalent display. Laser‐based array synthesis technology allows for flexible and rapid on‐surface synthesis of different peptides. By combining this technique with click chemistry, neo‐glycopeptides were produced directly on a functionalized glass slide in the microarray format. Density and spatial distribution of carbohydrates can be tuned, resulting in well‐defined glycan structures for multivalent display. The two lectins concanavalin A and langerin were probed with different glycans on multivalent scaffolds, revealing strong spacing‐, density‐, and ligand‐dependent binding. In addition, we could also measure the surface dissociation constant. This approach allows for a rapid generation, screening, and optimization of a multitude of multivalent scaffolds for glycan binding., Interactions of proteins with glycans rely on multivalency, where multiple adjacent binding events are involved. To study this glycan density‐dependent binding, a facile technique to synthesize peptide‐based multivalent carbohydrate scaffolds in parallel, directly on‐chip, in the microarray format, was developed. This allows to rapidly generate arrays of multivalent glycan structures, without the need for individual multistep syntheses per compound.

In this work, we present a qualitative and quantitative experimental analysis, as well as a numerical model, of a novel variant of the laser-induced forward transfer, which uses millisecond laser pulses. In this process, soft material nanolayer spots are transferred from a donor slide, which is coated with the soft material layer, to an acceptor slide via laser irradiation. This method offers a highly flexible material transfer to perform high-throughput combinatorial chemistry for the generation of biomolecule arrays. For the first time, we show visual evidence that the main transfer mechanism is contact-based, due to thermal surface expansion of the donor layer. Thus, the process is different from the many known variants of laser-induced forward transfer. We characterize the maximum axial surface expansion in relation to laser power and pulse duration. On this basis, we derive a numerical model that approximates the axial surface expansion within measurement tolerances. Finally, we analyze the topology of the transferred soft material nanolayer spots by fluorescence imaging and vertical scanning interferometry to determine width, height, and shape of the transferred material. Concluding from this experimental and numerical data, we can now predict the amount of transferred material in this process.

We developed a next-generation method for chemical in–situ combinatorial biomolecule array synthesis. This allows for an unprecedented combinatorial freedom in the automated chemical synthesis of molecule arrays with very high spot densities. Key feature of this new method is an automated positioning and laser transfer process: Small solid material spots are rapidly transferred from a donor film to an acceptor surface, requiring only minute amounts of materials. The transfer is performed with different and easy-to-produce donor slides. Each donor slide bears a thin polymer film, embedding one type of monomer. The coupling reaction occurs in a separate heating step, where the matrix becomes viscous and building blocks can diffuse within the material and couple to the acceptor surface. Since these transferred material spots are only several nanometers thin, this method allows for a consecutive multi-layer material deposition of e.g. activation reagents and amino acids. Subsequent heat-induced mixing facilitates an in–situ activation and coupling of the monomers. Positioning several of such resin spots, containing different chemical reagents, on top of each other, will enable for the first time in such small dimensions unique chemical synthesis strategies for each spot. Amount and concentration of the deposited materials can be adjusted with the laser parameters. Employing similar arrays, we can analyze the human immune response towards the proteome of different pathogens. We screened several peptide array replicas with different patient sera. The screenings resulted in significant hits in several proteins with interesting implications for future diagnostics and vaccine development.

Glycan microarrays have become a powerful technology to study biological processes, such as cell-cell interaction, inflammation, and infections. Yet, several challenges, especially in multivalent display, remain. In this introductory lecture we discuss the state-of-the-art glycan microarray technology, with emphasis on novel approaches to access collections of pure glycans and their immobilization on surfaces. Future directions to mimic the natural glycan presentation on an array format, as well as in situ generation of combinatorial glycan collections, are discussed.

A low-cost laser-based printing setup is presented, which allows for the spot-wise patterning of surfaces with defined polymer nanolayers. These nanolayer spots serve as a “solid solvent,” embedding different chemicals, chemical building blocks, materials, or precursors and can be stacked on top of each other. By melting the spot pattern, the polymer-embedded molecules are released for chemical reaction. This enables researchers to quickly pattern a surface with different molecules and materials, mixing them directly on the surface for high-throughput chemical synthesis to generate and screen diverse microarray libraries. In contrast to expensive ink-jet or contact printing, this approach does not require premixing of inks, which enables in situ combinatorial mixing. Easy access and versatility of this patterning approach are shown by generating microarrays of various biomolecules, such as glycans for the first time, to screen interactions of antibodies and lectins. In addition, a layer-by-layer solid-phase synthesis of peptides directly on the microarray is presented. Amino acid–containing nanolayers are repeatedly laser-transferred and reacted with the functionalized acceptor surface in defined patterns. This simple system enables a reproducible array production, down to spot-to-spot distances of 100 μm, and offers a flexible and cheap alternative to expensive spotting robot technology.

Elite Rhythmic Gymnasts (RGs) constitute a unique metabolic model and they are prone to developing Anorexia Athletica. The aim of the present study was to evaluate the effect of training intensity on salivary adiponectin levels and assess a possible role of salivary adiponectin levels as a predictive factor of reproductive dysfunction and bone mass acquisition in elite RGs. The study included 80 elite female RGs participating in the World Rhythmic Gymnastics Championship tournament held in Montpellier, France on September 2011. Anthropometric values were assessed, training data and menstrual pattern were recorded, bone mass was measured with Broadband ultrasound attenuation (dB/Mhz) and baseline salivary adiponectin levels were determined. The athletes were classified as intensely and very intensely trained, considering the mean training intensity (40.84h/week). Moreover, considering their reproductive status, they were divided into RG's with normal menstruation, primary amenorrhea and oligomenorrhea. All comparisons were adjusted to age, BMI and body fat percentage differences. Very intensely trained RGs showed higher salivary adiponectin levels (p=0.05). Moreover, salivary adiponectin levels showed significant correlation with training intensity (r=0.409, p=0.003). On the other hand, no association of salivary adiponectin levels was documented with either reproductive function or bone mass acquisition. The results of the present study suggest that, in elite RGs, salivary adiponectin levels are associated with the intensity of training, possibly reflecting the deterioration of energy balance rather than the training stress. On the other hand, a predictive role of salivary adiponectin levels in reproductive dysfunction or bone mass acquisition could not be supported.

Regular physical activity during puberty improves bone mass acquisition. However, it is unknown whether extreme intense training has the same favorable effect on the skeleton.We evaluated the bone mass acquisition in a unique cohort of world-class rhythmic gymnasts.A total of 133 adolescent girls and young women with a mean age of 18.7 ± 2.7 (14.4-26.7) years participated in this study: 82 elite rhythmic gymnasts (RGs) and 51 controls (CONs).Anthropometric variables and body composition were assessed, and all participants completed questionnaires on their general medical, menstrual, and training histories. Broadband ultrasound attenuation (BUA in decibels per megahertz) was determined by quantitative ultrasound at the heel.RGs presented lower weight (-8.5%, P.001), body mass index (-11.7%, P.001), and body fat mass (-43%, P.001) and higher muscle mass (6.3%, P.01) and height (+2.8 cm, P.01). RGs presented an age of menarche significantly delayed compared with CONs (15.6 ± 1.6 vs 12.7 ± 1.7 years; P.001) and a high prevalence of menstrual disorders (64%). BUA values were higher in RGs vs CONs (68.6 ± 4.6 and 65.4 ± 3.3 dB/Mhz, respectively; P.001). This difference was exacerbated when BUA was adjusted for age and body weight. BUA values in RGs were not affected by menstrual or training status. Among RGs with menarche, BUA was higher (71.5 ± 4.1 and 67.9 ± 3.5 dB/Mhz) for delayed (14.4 ± 0.8 years) vs severely delayed (17.3 ± 1.4 years) menarcheal age. BUA was positively correlated with body weight and body mass index and tended to be correlated with age.Conversely to expectations for adolescents and young women with a high prevalence of menstrual disorders and/or delayed menarche, intense training in rhythmic gymnastics appeared to have a beneficial effect on the bone health of a weight-bearing site. This effect was nevertheless modulated by the age of menarche. The high mechanical loading generated by this activity may counterbalance the negative effect of menstrual disorders.

Children with chronic liver disease (CLD) need a head to toe approach and an early suspicion of multi organ involvement. Nutritional assessment and management is the cornerstone of management. Consider immune dysfunction in everyday treatment decisions. Consider early heart-lung-brain involvement in transplant evaluation.

The aim of the study was to evaluate complication screening and follow-up patterns in a population with type 1 diabetes mellitus and celiac disease (T1D/CD) in relation to a matched cohort with celiac disease (CD) alone at our center.We retrospectively reviewed the health charts of 41 children with T1D and biopsy-proven CD and compared anthropometrics and complication of screening within 2 years from CD diagnosis. Follow-up patterns were determined 3 years postdiagnosis. This population was then compared with a population with both symptomatic and asymptomatic CD matched for age and sex.In comparison with T1D/CD, patients with CD alone had a significantly lower height, weight and body mass index (BMI z score 0.01 vs 0.81, P = 0.001) and higher rates of screening for anemia (95% vs 71%, P = 0.003) and bone health (49% vs 29%, P = 0.05). Minimal rates of laboratory abnormalities were observed in either group, irrespective of symptoms at presentation, but CD alone more often presented with anemia than T1D/CD. Repeat serology testing was significantly more frequently performed in the T1D/CD group. Follow-up was equally variable with a median of 3 (range 0-4) visits with a gastroenterologist during the first 3 years postdiagnosis.These results suggest that patients with T1D/CD represent a distinct and possibly milder phenotype from CD alone. Complication screening was variable and negative for the majority of the patients. Guidelines for follow-up may need to be tailored to specific groups to standardize evaluation and complication screening, especially with regard to bone health.