Mediating and Moderating Variables in the Relationship Between Emotional Demands and Teachers’ Emotional Exhaustion / [Variables mediadoras y moderadoras de la relación entre exigencias emocionales y agotamiento emocional en docentes]

Teachers tend to suffer high levels of emotional exhaustion, a variable that is associated with poor mental health and lower job performance. The present study analyzed how emotional demands, emotional dissonance, and self-efficacy to cope with stress interact in predicting teachers’ emotional exhaustion. To conduct this longitudinal research, 108 Andalusian teachers (57.3% women; mean age = 45.30, SD = 8.68) completed an online survey at three different time points. Moderated mediation analysis suggested that emotional dissonance mediated the relationship between emotional demands and emotional exhaustion, with self-efficacy acting as a moderator between the two. Teachers who perceived high emotional demands saw their levels of emotional dissonance increase, which in turn led to an increase in emotional exhaustion. In addition, self-efficacy acted as a protective factor against emotional exhaustion, buffering the negative effect of emotional dissonance. Strengthening these protective variables through interventions that increase levels of self-efficacy to cope with stress and reduce levels of emotional dissonance could help prevent teachers’ emotional exhaustion.(AU)

Los docentes tienden a sufrir un nivel elevado de agotamiento emocional, variable que se asocia con una mala salud mental y un bajo desempeño laboral. El estudio analiza cómo interactúan en la prevención del agotamiento emocional de los docentes las exigencias emocionales, la disonancia emocional y la autoeficacia para afrontar el estrés. Para llevar a cabo esta investigación de carácter longitudinal, 108 profesores andaluces (57.3% mujeres, edad media = 45.30, DT = 8.68) cumplimentaron una encuesta online en tres momentos distintos. El análisis de mediación moderada indicaba que la disonancia emocional mediaba la relación existente entre las exigencias emocionales y el agotamiento emocional, actuando como moderadora entre ambos la autoeficacia. Los profesores que percibieron exigencias emocionales elevadas vieron aumentar su grado de disonancia emocional, lo que a su vez aumentó el agotamiento emocional. Además, la autoeficacia actuó como factor protector del agotamiento emocional, amortiguando el efecto negativo de la disonancia emocional. Reforzar estas variables protectoras a través de intervenciones que aumenten el grado de autoeficacia para afrontar el estrés y reduzcan la disonancia emocional podría ayudar a prevenir el agotamiento emocional de los docentes.(AU)

Lyophilization cycle design for highly concentrated protein formulations supported by micro freeze-dryer and heat flux sensor.

High-concentration protein formulations (HCPFs) represent a common strategy and freeze-drying can mitigate the stability challenges of HCPFs. In general, an in-depth characterization of the lyophilization process is essential to not impair the product quality by inappropriate process parameters. The aim of this study was to create a primary drying design space for lyophilized HCPFs by utilizing the heat flux sensor (HFS) integrated in a MicroFD with a minimum number of cycles and product vials. All the necessary data to obtain the design space were determined starting from only two lyophilization cycles, each holding 19 vials. The vial heat transfer coefficient (Kv) was determined by the HFS and compared to gravimetric values. The results indicate a consistant offset between the HFS and the gravimetry based values for annealed samples with higher protein content. This work highlights a possibility of integrating new technologies, the HFS and the MicroFD to generate a design space for lyophilization of HCPFs, which enables to implement a QbD approach at minimal material and time investment.

Risk and protective factors of emotional exhaustion in teachers. A moderating mediation on emotional exhaustion / Los factores de riesgo y protectores del agotamiento emocional en el profesorado. Un modelo de mediación moderada del agotamiento emocional

Emotional exhaustion negatively influences teachers' professional development. The main aim of this study was to analyze how the perception of attention to diversity, emotional dissonance, and social support were related to emotional exhaustion. To carry out this study, 567 teachers (64.9% women, mean age = 44.80, SD = 0.48) answered a questionnaire. Emotional dissonance mediated the relationships that established with emotional exhaustion the perception of attention to diversity (a) derived from special educational needs and (b) derived from cultural diversity. These mediations were moderated by social support, by confirming the interaction effect between social support and (a) the perception of attention to cultural diversity and (b) emotional dissonance. Teachers' perceptions of having to attend to diversity and not being able to express the real emotions they feel to students are stressor factors that influence emotional exhaustion levels. Moreover, social support acts as a protective factor that diminishes the negative effects of perception of attention to diversity and emotional dissonance on emotional exhaustion. These results highlight the need to promote strong support networks in educational settings within the center's cloister, to stimulate a healthier educational environment that reverts to lower levels of emotional exhaustion among teachers.(AU)

El agotamiento emocional influye negativamente en el desarrollo profesional de los docentes. El objetivo principal de este estudio fue analizar cómo se relacionaban con el agotamiento emocional la percepción de atención a la diversidad, la disonancia emocional y el apoyo social. Para llevar a cabo el estudio, 567 docentes (64.9% mujeres; edad media = 44.80, DT = 0.48) respondieron a un cuestionario. La disonancia emocional medió las relaciones establecidas entre la percepción de la atención a la diversidad derivada (a) de las necesidades educativas especiales y (b) de la diversidad cultural y el agotamiento emocional. Esta mediación fue moderada por el apoyo social, al confirmarse el efecto de interacción entre el apoyo social y (a) la apreciación de atención a la diversidad cultural y (b) la disonancia emocional. La apreciación de los docentes de que tenían que atender a la diversidad y de que no podían expresar al alumnado sus emociones reales constituye un factor estresante que influye en el grado de agotamiento emocional. Además, el apoyo social actúa como factor protector que disminuye el efecto negativo que ejercen la percepción de la atención a la diversidad y la disonancia emocional en el agotamiento emocional. Los resultados ponen de manifiesto la necesidad de promover fuertes redes de apoyo en los escenarios educativos en el claustro del centro para favorecer un ambiente educativo más saludable que revierta en un menor agotamiento emocional en los docentes.(AU)

Burnout and Self-Perceived Stress in Workers in Essential Services after the Impact of Hurricanes Irma and Maria.

OBJECTIVE: To examine the levels of burnout and self-perceived stress in workers at the Puerto Rico Electric Power Authority, who experienced major disasters: Hurricanes Irma and Maria. METHODS: A quantitative descriptive cross-sectional study with a non-probabilistic convenience sample was conducted in workers at the Puerto Rico Electric Power Authority. A structured questionnaire was administered to a sample of 163 eligible participants, aged 21 years and older, who participated voluntarily. Using employees of the electric company, the study examined the relationships between burnout and several characteristics (years of employment, existing health conditions, and coping strategies) both before and after Hurricanes Irma and Maria. Burnout was assessed with Gil-Monte's Spanish Burnout Inventory, and self-perceived stress was assessed with the 14-item Perceived Stress Scale. RESULTS: Before the hurricanes, 16.6% of the workers reported high levels of burnout syndrome, while, after the hurricanes, the proportion increased to one-fifth (20.9%). Prior to the 2 hurricanes, more than one-fourth (23.4%) of the sample reported being extremely stressed; after the hurricanes, that proportion increased to 55%. Factors such as years of employment, counseling, and self-perceived stress showed significant statistical associations (P < .05) with burnout. CONCLUSION: From a public health standpoint, priority should be given to this population, thereby preventing burnout and any other negative effects of the aftermath (i.e., the lengthy response, recovery, and reconstruction) of these kinds of major disaster.

Design of freeze-drying cycles: The determination of heat transfer coefficient by using heat flux sensor and MicroFD.

The complexity of biopharmaceuticals requires often the freeze-drying as stabilizing process. Inadequate parameters in the primary drying phase can impair product quality, besides, increasing time and costs. Therefore, the process requires a thorough characterization and with this purpose, heat flux sensor (HFS) and miniaturized freeze-dryers conceived to emulate larger equipment, were recently introduced. Our study investigates, for the first time, the use of HFS and miniaturized freeze-dryer (MicroFD) in combination to obtain the heat transfer coefficient (Kv) for two formulation types and freezing protocols. First, as the MicroFD presents the possibility to set the temperature of vial surrounding (LyoSIM), it was determined which set-up was representative for a lab-scale freeze drying process. Additionally, the HFS-based results were compared with the data obtained by the most accurate, but time-consuming and invasive gravimetric method. Second, the role of atypical heat transfer was evaluated for HFS and gravimetric methodology with gold-coated and un-coated vials. Obtained results revealed the HFS and the MicroFD can be used in combination to obtain Kv real-time with much less effort that gravimetrically, to study different vial scenarios, and to design lyophilization processes with a limited amount of material and experiments.

Detecting chromosomal interactions in Capture Hi-C data with CHiCAGO and companion tools.

Capture Hi-C is widely used to obtain high-resolution profiles of chromosomal interactions involving, at least on one end, regions of interest such as gene promoters. Signal detection in Capture Hi-C data is challenging and cannot be adequately accomplished with tools developed for other chromosome conformation capture methods, including standard Hi-C. Capture Hi-C Analysis of Genomic Organization (CHiCAGO) is a computational pipeline developed specifically for Capture Hi-C analysis. It implements a statistical model accounting for biological and technical background components, as well as bespoke normalization and multiple testing procedures for this data type. Here we provide a step-by-step guide to the CHiCAGO workflow that is aimed at users with basic experience of the command line and R. We also describe more advanced strategies for tuning the key parameters for custom experiments and provide guidance on data preprocessing and downstream analysis using companion tools. In a typical experiment, CHiCAGO takes ~2-3 h to run, although pre- and postprocessing steps may take much longer.

Zebrafish Model as a Screen to Prevent Cyst Inflation in Autosomal Dominant Polycystic Kidney Disease.

In autosomal dominant polycystic kidney disease (ADPKD), kidney cyst growth requires the recruitment of CFTR (cystic fibrosis transmembrane conductance regulator), the chloride channel that is defective in cystic fibrosis. We have been studying cyst inflation using the zebrafish Kupffer's vesicle (KV) as model system because we previously demonstrated that knocking down polycystin 2 (PC2) induced a CFTR-mediated enlargement of the organ. We have now quantified the PC2 knockdown by showing that it causes a 73% reduction in the number of KV cilia expressing PC2. According to the literature, this is an essential event in kidney cystogenesis in ADPKD mice. Additionally, we demonstrated that the PC2 knockdown leads to a significant accumulation of CFTR-GFP at the apical region of the KV cells. Furthermore, we determined that KV enlargement is rescued by the injection of Xenopus pkd2 mRNA and by 100 µM tolvaptan treatment, the unique and approved pharmacologic approach for ADPKD management. We expected vasopressin V2 receptor antagonist to lower the cAMP levels of KV-lining cells and, thus, to inactivate CFTR. These findings further support the use of the KV as an in vivo model for screening compounds that may prevent cyst enlargement in this ciliopathy, through CFTR inhibition.

CiliarMove: new software for evaluating ciliary beat frequency helps find novel mutations by a Portuguese multidisciplinary team on primary ciliary dyskinesia.

Evaluation of ciliary beat frequency (CBF) performed by high-speed videomicroscopy analysis (HVMA) is one of the techniques required for the correct diagnosis of primary ciliary dyskinesia (PCD). Currently, due to lack of open-source software, this technique is widely performed by visually counting the ciliary beatings per a given time-window. Our aim was to generate open-source, fast and intuitive software for evaluating CBF, validated in Portuguese PCD patients and healthy volunteers. Nasal brushings collected from 17 adult healthy volunteers and 34 PCD-referred subjects were recorded using HVMA. Evaluation of CBF was compared by two different methodologies: the new semi-automated computer software CiliarMove and the manual observation method using slow-motion movies. Clinical history, nasal nitric oxide and transmission electron microscopy were performed for diagnosis of PCD in the patient group. Genetic analysis was performed in a subset (n=8) of suspected PCD patients. The correlation coefficient between the two methods was R2=0.9895. The interval of CBF values obtained from the healthy control group (n=17) was 6.18-9.17 Hz at 25°C. In the PCD-excluded group (n=16), CBF ranged from 6.84 to 10.93 Hz and in the PCD group (n=18), CBF ranged from 0 to 14.30 Hz. We offer an automated open-source programme named CiliarMove, validated by the manual observation method in a healthy volunteer control group, a PCD-excluded group and a PCD-confirmed group. In our hands, comparisons between CBF intervals alone could discern between healthy and PCD groups in 78% of the cases.

Pkd2 Affects Cilia Length and Impacts LR Flow Dynamics and Dand5.

The left-right (LR) field recognizes the importance of the mechanism involving the calcium permeable channel Polycystin-2. However, whether the early LR symmetry breaking mechanism is exclusively via Polycystin-2 has not been tested. For that purpose, we need to be able to isolate the effects of decreasing the levels of Pkd2 protein from any eventual effects on flow dynamics. Here we demonstrate that curly-up (cup) homozygous mutants have abnormal flow dynamics. In addition, we performed one cell stage Pkd2 knockdowns and LR organizer specific Pkd2 knockdowns and observed that both techniques resulted in shorter cilia length and abnormal flow dynamics. We conclude that Pkd2 reduction leads to LR defects that cannot be assigned exclusively to its putative role in mediating mechanosensation because indirectly, by modifying cell shape or decreasing cilia length, Pkd2 deficit affects LR flow dynamics.

Heat flux sensor to create a design space for freeze-drying development.

Freeze-drying methodology requires an in-depth understanding and characterization for optimal processing of biopharmaceuticals. Particularly the primary drying phase, the longest and most expensive stage of the process, is of interest for optimization. The currently used process analytical technology (PAT) tools give highly valuable insights but come with limitations. Our study describes, for the first time, the application of a heat flux sensor (HFS) to build a primary drying design space and predict the process evolution. First, the heat transfer coefficient (Kv) generated by HFS and by the most accurate, but time-consuming and invasive, gravimetric method were compared. Second, the applicability to generate a design space was tested and verified. Obtained results revealed a good agreement of the values generated from this new and fast HFS compared to the gravimetric determination. Additionally, residual moisture assessed by Karl-Fischer titration and frequency modulated spectroscopy (FMS) support the quality of the obtained predictions. Thus, the HFS approach can substantially accelerate evaluation, development and transfer of a freeze-drying cycle.

Evaluation of Sucrose Laurate as an Intestinal Permeation Enhancer for Macromolecules: Ex Vivo and In Vivo Studies.

Oral delivery of macromolecules requires permeation enhancers (PEs) adaptable to formulation. Sucrose laurate (SL) (D1216), a food grade surfactant, was assessed in Caco-2 monolayers, isolated rat intestinal tissue mucosae, and rat intestinal instillations. Accordingly, 1 mM SL increased the apparent permeability coefficient (Papp) of [14C]-mannitol and reduced transepithelial electrical resistance (TEER) across monolayers. It altered expression of the tight junction protein, ZO-1, increased plasma membrane potential, and decreased mitochondrial membrane potential in Caco-2 cells. The concentrations that increased flux were of the same order as those that induced cytotoxicity. In rat colonic tissue mucosae, the same patterns emerged in respect to the concentration-dependent increases in paracellular marker fluxes and TEER reductions with 5 mM being the key concentration. While the histology revealed some perturbation, ion transport capacity was retained. In rat jejunal and colonic instillations, 50 and 100 mM SL co-administered with insulin induced blood glucose reductions and achieved relative bioavailability values of 2.4% and 8.9%, respectively, on a par with the gold standard PE, sodium caprate (C10). The histology of the intestinal loops revealed little damage. In conclusion, SL is a candidate PE with high potential for emulsion-based systems. The primary action is plasma membrane perturbation, leading to tight junction openings and a predominant paracellular flux.

An oral alpha-galactosylceramide adjuvanted Helicobacter pylori vaccine induces protective IL-1R- and IL-17R-dependent Th1 responses.

Helicobacter pylori causes chronic gastric infection that can lead to peptic ulcers and is an identified risk factor for gastric cancer development. Although much effort has been put into the development of a Helicobacter pylori vaccine over the last three decades, none has yet reached clinical application. Specific challenges pertaining to effective H. pylori vaccine development include the lack of proven vaccine-effective antigens and safe mucosal adjuvants to enhance local immune responses as well as the lack of accepted correlates of protection. Herein, we demonstrate that prophylactic intragastric immunisation with a whole-cell killed H. pylori antigen administered together with the non-toxic oral adjuvant α-galactosylceramide (α-GalCer) induced effective immune protection against H. pylori infection in mice, which was of similar magnitude as when using the "gold standard" cholera toxin as adjuvant. We further describe that this α-GalCer-adjuvanted vaccine formulation elicited strong intestinal and systemic Th1 responses as well as significant antigen-specific mucosal and systemic antibody responses. Finally, we report that the protective intestinal Th1 responses induced by α-GalCer are dependent on CD1d, IL-1R as well as IL-17R signalling. In summary, our results show that α-GalCer is a promising adjuvant for inclusion in an oral vaccine against H. pylori infection.

Alpha-galactosylceramide enhances mucosal immunity to oral whole-cell cholera vaccines.

Cholera is a severe diarrheal disease caused by the bacterium Vibrio cholerae (V. cholerae) that results in 3-4 million cases globally with 100,000-150,000 deaths reported annually. Mostly confined to developing nations, current strategies to control the spread of cholera include the provision of safe drinking water and improved sanitation and hygiene, ideally in conjunction with oral vaccination. However, difficulties associated with the costs and logistics of these strategies have hampered their widespread implementation. Specific challenges pertaining to oral cholera vaccines (OCVs) include a lack of safe and effective adjuvants to further enhance gut immune responses, the complex and costly multicomponent vaccine manufacturing, limitations of conventional liquid formulation and the lack of an integrated delivery platform. Herein we describe the use of the orally active adjuvant α-Galactosylceramide (α-GalCer) to strongly enhance intestinal bacterium- and toxin-specific IgA responses to the OCV, Dukoral® in C57BL/6 and BALB/c mice. We further demonstrate the mucosal immunogenicity of a novel multi-antigen, single-component whole-cell killed V. cholerae strain and the enhancement of its immunogenicity by adding α-GalCer. Finally, we report that combining these components and recombinant cholera toxin B subunit in the SmPill® minisphere delivery system induced strong intestinal and systemic antigen-specific antibody responses.

BabA-mediated adherence of pediatric ulcerogenic H. pylori strains to gastric mucins at neutral and acidic pH.

Helicobacter pylori infection can result in non-ulcer dyspepsia (NUD), peptic ulcer disease (PUD), adenocarcinoma, and gastric lymphoma. H. pylori reside within the gastric mucus layer, mainly composed of mucins carrying an array of glycan structures that can serve as bacterial adhesion epitopes. The aim of the present study was to characterize the binding ability, adhesion modes, and growth of H. pylori strains from pediatric patients with NUD and PUD to gastric mucins. Our results showed an increased adhesion capacity of pediatric PUD H. pylori strains to human and rhesus monkey gastric mucins compared to the NUD strains both at neutral and acidic pH, regardless if the mucins were positive for Lewis b (Leb), Sialyl-Lewis x (SLex) or LacdiNAc. In addition to babA positive strains being more common among PUD associated strains, H. pylori babA positive strains bound more avidly to gastric mucins than NUD babA positive strains at acidic pH. Binding to Leb was higher among babA positive PUD H. pylori strains compared to NUD strains at neutral, but not acidic, pH. PUD derived babA-knockout mutants had attenuated binding to mucins and Leb at acidic and neutral pH, and to SLex and DNA at acidic pH. The results highlight the role of BabA-mediated adherence of pediatric ulcerogenic H. pylori strains, and points to a role for BabA in adhesion to charged structures at acidic pH, separate from its specific blood group binding activity.

Tri-methylation of histone H3 lysine 4 facilitates gene expression in ageing cells.

Transcription of protein coding genes is accompanied by recruitment of COMPASS to promoter-proximal chromatin, which methylates histone H3 lysine 4 (H3K4) to form H3K4me1, H3K4me2 and H3K4me3. Here, we determine the importance of COMPASS in maintaining gene expression across lifespan in budding yeast. We find that COMPASS mutations reduce replicative lifespan and cause expression defects in almost 500 genes. Although H3K4 methylation is reported to act primarily in gene repression, particularly in yeast, repressive functions are progressively lost with age while hundreds of genes become dependent on H3K4me3 for full expression. Basal and inducible expression of these genes is also impaired in young cells lacking COMPASS components Swd1 or Spp1. Gene induction during ageing is associated with increasing promoter H3K4me3, but H3K4me3 also accumulates in non-promoter regions and the ribosomal DNA. Our results provide clear evidence that H3K4me3 is required to maintain normal expression of many genes across organismal lifespan.

Thermostability of the coating, antigen and immunostimulator in an adjuvanted oral capsule vaccine formulation.

Oral vaccines present an attractive alternative to injectable vaccines for enteric diseases due to ease of delivery and the induction of intestinal immunity at the site of infection. However, susceptibility to gastrointestinal proteolysis, limited transepithelial uptake and a lack of clinically acceptable adjuvants present significant challenges. A further challenge to mass vaccination in developing countries is the very expensive requirement to maintain the cold chain. We recently described the effectiveness of a Single Multiple Pill® (SmPill®) adjuvanted capsule approach to enhance the effectiveness of a candidate enterotoxigenic Escherichia coli (ETEC) oral vaccine. Here it was demonstrated that this delivery system maintains the antigenicity of ETEC colonisation factor antigen I (CFA/I) and the immunostimulatory activity of the orally active α-Galactosylceramide (α-GalCer) adjuvant after storage of SmPill® minispheres under room temperature and extreme storage conditions for several months. In addition, the internal structure of the cores of SmPill® minispheres and antigen release features at intestinal pH were found to be preserved under all these conditions. However, changes in the surface morphology of SmPill® minispheres leading to the antigen release at gastric pH were observed after a few weeks of storage under extreme conditions. Those modifications were prevented by the introduction of an Opadry® White film coating layer between the core of SmPill® minispheres and the enteric coating. Under these conditions, protection against antigen release at gastric pH was maintained even under high temperature and humidity conditions. These results support the potential of the SmPill® minisphere approach to maintain the stability of an adjuvanted whole cell killed oral vaccine formulation.

Notch/Her12 signalling modulates, motile/immotile cilia ratio downstream of Foxj1a in zebrafish left-right organizer.

Foxj1a is necessary and sufficient to specify motile cilia. Using transcriptional studies and slow-scan two-photon live imaging capable of identifying the number of motile and immotile cilia, we now established that the final number of motile cilia depends on Notch signalling (NS). We found that despite all left-right organizer (LRO) cells express foxj1a and the ciliary axonemes of these cells have dynein arms, some cilia remain immotile. We identified that this decision is taken early in development in the Kupffer's Vesicle (KV) precursors the readout being her12 transcription. We demonstrate that overexpression of either her12 or Notch intracellular domain (NICD) increases the number of immotile cilia at the expense of motile cilia, and leads to an accumulation of immotile cilia at the anterior half of the KV. This disrupts the normal fluid flow intensity and pattern, with consequent impact on dand5 expression pattern and left-right (L-R) axis establishment.

Connecting high-temperature and low-temperature protein stability and aggregation.

Protein aggregation is a long-standing problem for preservation of proteins in both laboratory settings and for commercial biotechnology products. It is well established that heating (cooling) can accelerate (slow) aggregation by populating (depopulating) unfolded or partially unfolded monomer states that are key intermediates in aggregation processes. However, there is a long-standing question of whether the same mechanism(s) that lead to aggregation under high-temperature stress are relevant for low-temperature stress such as in refrigerated or supercooled liquids. This report shows the first direct comparison of "hot" and "cold" aggregation kinetics and folding/unfolding thermodynamics, using bovine hemoglobin as a model system. The results suggest that the same mechanism for non-native aggregation holds from "hot" to "cold" temperatures, with an aggregation temperature-of-maximum-stability slightly below 0°C. This highlights that sub-zero temperatures can induce cold-mediated aggregation, even in the absence of freezing stresses. From a practical perspective, the results suggests the possibility that cold-stress may be a useful alternative to heat-stress for extrapolating predictions of protein shelf life at refrigerated conditions, as well as providing a foundation for more mechanistic studies of cold-stress conditions in future work. A comparison between isochoric and isobaric methods is also briefly discussed.

Role of the sugar moiety on the opioid receptor binding and conformation of a series of enkephalin neoglycopeptides.

Glycosylation by simple sugars is a drug discovery alternative that has been explored with varying success for enhancing the potency and bioavailability of opioid peptides. Long ago we described two O-glycosides having either ß-Glucose and ß-Galactose of (d-Met2, Pro5)-enkephalinamide showing one of the highest antinociceptive activities known. Here, we report the resynthesis of these two analogs and the preparation of three novel neoglycopeptide derivatives (α-Mannose, ß-Lactose and ß-Cellobiose). Binding studies to cloned zebrafish opioid receptors showed very small differences of affinity between the parent compound and the five glycopeptides thus suggesting that the nature of the carbohydrate moiety plays a minor role in determining the binding mode. Indeed, NMR conformational studies, combined with molecular mechanics calculations, indicated that all glycopeptides present the same major conformation either in solution or membrane-like environment. The evidences provided here highlight the relevance for in vivo activity of the conjugating bond between the peptide and sugar moieties in opioid glycopeptides.