Elastic knee sleeves are often worn following anterior cruciate ligament (ACL) reconstruction. The study aimed to define immediate and 6-week effects of wearing a knee sleeve on ground reaction forces (GRF) and knee joint power during a step-down hop task.Using a cross-over design, we estimated GRF and knee kinematics and kinetics during a step-down hop for 30 participants following ACL reconstruction (median 16 months post-surgery) with and without wearing a knee sleeve. In a subsequent randomised clinical trial, participants in the ‘Sleeve Group’ (n = 9) wore the sleeve for 6 weeks at least 1 hour daily, while a ‘Control Group’ (n = 9) did not wear the sleeve. We compared the following outcomes using statistical parametric mapping (SPM): (1) GRF and knee joint power trajectories between three conditions at baseline ; (2) GRF and knee joint power trajectories within-participant changes from baseline to follow-up between groups. We also compared discrete peak GRFs and power, rate of  force development, and mean knee joint power in the first 5% of stance phase.SPM showed no differences for GRF for the (unsleeved) injured compared to the uninjured sides; when wearing the sleeve, injured side mean power in the first 5% of stance increased significantly from a concentric to an eccentric power. Discrete variables showed lower peak anterior (propulsive) GRF, mean power in the first 5% of stance, peak eccentric and concentric power for the injured compared to the uninjured sides. After six weeks, a directional change for vertical GRF differed showed slightly decreased forces for the Control Group and increased forces for the Sleeve Group.Wearing a knee sleeve on the anterior cruciate ligament injured knee improved knee power during the first 5% of stance during the step-down hop. No consistent changes were observed for ground reaction forces for SPM and discrete variable analyses. Wearing the knee sleeve at least one hour daily for 6-weeks lead to a directional change of increased vertical GRF for the Sleeve Group at follow-up.ACTRN12618001083280, 28/06/2018. https: //anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375347&isClinicalTrial=False.The trial was prospectively registered with the Australia New Zealand Clinical Trials Registry No:  Rupture of the anterior cruciate ligament (ACL) is a debilitating knee injury with potentially devastating short-term and long-term consequences. Rehabilitation following ACL reconstruction includes individualised progressive exercise prescription to improve range of motion, muscle strength, sensori-motor control and sports- and work-specific skills, as well as physical fitness . StrategJump-landing strategies have received substantial attention as a risk factor for ACL rupture and as outcomes following such injury , 14. CurDuring jump landing, power is absorbed by the lower extremity, and, during take-off, power is generated. Lower knee range of motion decreases the range over which force can be generated, potentially leading to lower peak knee moments and knee power , 23. FolExploring the effects of wearing a knee sleeve during the step-down hop showed no changes for sagittal plane knee moments, yet participants landed with more knee flexion during landing while wearing a knee sleeve compared to the control condition . In thisBased on our previous finding of lower external knee flexion moments for the injured side , our prith June 2018). We follow CONSORT reporting guidelines [This is the third paper in a sequence of papers stemming from a single, multi-year study exploring the influence of wearing a knee sleeve for people with ACLR. This paper differs from the previous papers , 9 in thidelines . We repeThe study had two linked parts and all participants were involved in both parts. Part 1 consisted of a cross-over laboratory-based study, to examine immediate effects of the wearing of the knee sleeve on single-leg hop distance  and kneehttps: //trialfacts.com/). Volunteers completed a questionnaire  via REDCap prior to attending the first laboratory session. The questionnaire included demographics, injury and surgery history, the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) [We recruited participants via community advertising and the research participant recruitment agency TrialFacts (KDC-SKF)  and the KDC-SKF) . The TegWe recruited men and women, aged 18–40 years, who underwent ACL reconstruction within 6 months to 5 years previously. We specifically sought individuals who had not yet reached full functional level, defined for the purpose of this study by a score between 40 to 80/100 on the IKDC-SKF , 27, 28.2. Participants found to have an IKDC-SKF score less than 40  or greater than 80/100  were excluded.Participants were excluded if they had undergone a revision ACL reconstruction of the same knee (due to re-injury), or a previous ACL reconstruction of the opposite knee; self-reported any other lower limb, pelvic or low back musculoskeletal injuries or disorders that required medical care over the past 6 months; had known systemic, neurological or cardiovascular disorders; or had a body mass index (BMI) greater than 30 kg/mParticipants were individually randomised twice  with equal numbers in each group for both allocations. Block randomisation (in groups of 8 participants) was undertaken sequentially by a research officer using an electronic random number generator prior to participants being entered into the study. Each group was stratified by sex. The research officer informed the researcher responsible for the laboratory data collection of the order for the conditions for the cross-over trial, and the group allocation (for the RCT) via email prior to the start of the individual participant’s first laboratory session.Eligibility to be included was confirmed and participants provided written informed consent at the start of the first session. Participants were asked to be dressed in a singlet, a pair of shorts and their own sport shoes. Body mass and height were measured during the baseline session.Participants undertook two hopping tasks; a maximum horizontal single leg hop and a stub-maximum step-down hop. Participants practised the hopping tasks at sub-maximal distance with the uninjured and injured sides until they were confident with performing them as part of familiarisation and warm-up. They performed the maximum horizontal hop prior to undertaking the step-down-hop.Participants were informed of their group allocation for the RCT on completion of the first laboratory session. Following the 6-week period, all participants were asked to return to the laboratory to repeat the above assessments, repeating the hopping tasks (without wearing the knee sleeve).® AG, Zeulenroda-Triebes, Germany), a CE-certified medical device. For Part 1 , all participants performed the step-down hop with and without the sleeve. For Part 2 (RCT), participants of the ‘Sleeve Group’ (intervention) were instructed to wear the knee sleeve while performing their rehabilitative exercises, physical activity and sports, with a minimum of 1 hour per day for the 6-week period; the control group were not provided with a sleeve during this period.The intervention entailed use of the commercially available GenuTrain , sampling at 120 Hz, and Cortex 4.4 software . This was synchronized with a floor-mounted tri-axial force plate , sampling at 2,400 Hz. Cortex 5.5 was used to track and label the markers, and the biomechanical model, kinematic (joint angles) and kinetic (moments) variables were calculated using Visual3D Professional v6 . Here we report the procedures only for the force plate data.The participants were asked to stand on a 30-cm box, placed 15 cm from the force plate, and performed a step-down hop (adapted from Kristianslund and Krosshaug ) onto thGRF data from the stance phase of the hop is of interest; the start and end of the stance phase were defined by the vertical component of the GRF exceeding and returning below 20 N, respectively. Based on the SPM analysis the following discrete variables were extracted: rate of force development, mean joint power during the first 5% of stance, peak eccentric joint power and peak concentric joint power. The mean of five trials for each limb (injured versus uninjured) and condition (sleeved and unsleeved) for each participant along with descriptive variables were calculated.x, y, and z components of the ground reaction force data during stance were analysed for immediate effects (Part 1) and 6-week effects (Part 2). Force data were time-normalised to 1001 data points for each participant and condition (baseline) or session (follow-up). The mean time of all first and second vertical GRF peaks (Fz peaks), relative to the mean length of all trials, were used to time-align the respective Fz peaks for each trial. Therefore, data were time-normalised with MATLAB R2022a  in three phases to ensure comparison of equivalent events in the movement. For trials with only one Fz peak, standard time-normalisation to 1001 frames was performed.The JP(t) = xM(t)⋅xω(t), where JP is joint power at each time t, xM is the knee flexion-extension moment  and xω is knee flexion-extension angular velocity. By convention a knee  flexion moment is positive, and a flexing knee has a positive angular velocity, thus positive joint power indicates a net eccentric muscle contraction at the joint and negative joint power indicates a concentric contraction.Joint power was analysed as a follow-up to the GRF presented in this report and the kinetic, kinematic and temporal variables in previous reports. We investigated joint power in the sagittal plane as http: //spm1d.org/; Pataky, 2012) [The sample size calculation was based on the primary outcome of the larger study, namely maximal horizontal single leg jump distance, as reported previously . For oury, 2012) . Mean try, 2012) .T2 test was performed on the GRF components within each baseline condition [We determined immediate effects by two-way comparisons across the three combinations of sleeved injured leg, unsleeved injured leg, uninjured leg. The SPM time-continuous Hotellings ondition , 33. SPMondition .T2 test on the three-dimensional force difference trajectories comparing Sleeve and Control groups [post-hoc time-continuous t-tests to determine which conditions differed.Six-week effects were determined by calculating the mean, time-normalised GRF curves for each component, as with the immediate effects, and subtracting the baseline from the follow-up session, leaving ‘difference’ trajectories. We performed a time-continuous Hotellings l groups , 33. Fort-tests. Six-week effects were determined by time-continuous independent t-tests on the joint power difference trajectories. SPM calculations were performed using the spm1d package version M.0.4.8 . A conservative Bonferroni threshold of 0.017 was adopted to correct for multiple comparisons across the three GRF components and for knee joint power.Sagittal plane joint power is a one-dimensional, time-continuous variable so immediate effects were determined with multiple time-continuous paired Fz increases from initial contact to the first Fz peak. We defined the RFD as the first Fz peak divided by the time duration from landing force to the first Fz peak [Fz peak a time duration of 100 ms was used.Post hoc analyses were performed for the pre-defined GRF and knee joint power discrete variables, and those that were deemed to be of interest from the SPM analysis. Time-based variables included the Rate of Force Development (RFD). The RFD reflects the speed at which  Fz peak . For trit-tests and a Bonferroni correction across the three pairwise tests assessed between-condition effects.To investigate the immediate effects of wearing a knee sleeve, we used one-way repeated measures ANOVAs to compare three conditions at the baseline: (a) uninjured side, unsleeved to (b) injured side, unsleeved, and (c) injured side, sleeved. Sex  and time since ACL reconstruction (in months) were entered as co-variates. If Mauchley’s test for sphericity was significant (p≤ 0.05), the Greenhouse-Geisser correction was used. Post-hoc pairwise analyses using paired Individual change scores from baseline to follow-up were calculated for the dependent variables of the GRF and knee joint power. Due to low sample size (n = 9 per group) the change scores were compared between the intervention and the control groups using Mann-Whitney U tests for each outcome. The alpha level were set at p≤0.05. These analyses and those of demographic data were performed with SPSS Version 28.0.1.0 .We assessed 34 participants at baseline, but data for four participants were excluded from this analysis due to technical issues. Two participants of the Sleeve Group withdrew from the study following baseline assessment due to knee re-injuries, unrelated to use of the knee sleeve . Eight pThe SPM analysis found no statistical differences between any GRF components for any of the baseline conditions Figs –4.post-hoc testing. For peak Fy Posterior, no significant differences between sides and between conditions were found in pot-hoc testing. The (unsleeved) injured side had lower peak Fy Anterior (0.237 ± 0.097 N/BW) compared to the uninjured side (0.270 ± 0.087 N/BW), and wearing the sleeve showed no statistically significant effect for the injured side.For the discrete variables, significant effects were found for RFD, and peak anterior and posterior GRFs . Althougp = 0.017 threshold (The absorption phase (first phase) of stance entails eccentric quadriceps contraction, followed by a force generation (second) phase entailing concentric quadriceps contraction. Based on the SPM analysis, with one exception, there were no significant differences between the (unsleeved) injured and uninjured sides , betweenhreshold . At thatThe difference for the knee power in the first 5% of the stance phase when comparing injured to uninjured side is also evident with the discrete variable analysis . When weBased on the SPM analysis, there were no significant differences between the change in GRF from baseline to follow-up comparing the Sleeve group to the Control group . SimilarFy Anterior for the Control Group at follow-up. Comparing mean differences from baseline to follow-up between the groups, a difference in the response is apparent between the two groups for the peak Fy Anterior, as well as the peak vertical GRF (peak Fz). While peak Fy Anterior increased for the Control Group, a (non-significant) decrease is evident for the Sleeve Group. For peak Fz Vertical, there was a (non-significant) decrease for the Control Group, and a (non-significant) increase for the Sleeve Group. For knee joint power in the first 5% of stance, no significant differences were seen in both groups and between the groups.Discrete variable analyses of the baseline to follow-up changes suggest no significant difference within the groups respectively, based on the 95% confidence intervals for GRF and knee joint power variables , except direction of the change of the vertical GRF: while the Sleeve Group showed increased vertical GRF at follow-up, those of the Control group decreased. The differences within each group were not significant, based on the 95% confidence intervals. Thirdly, for the Control Group only, at 6-week follow-up they had increased peak Fy anterior GRF. No other significant differences in changes between the Sleeve Group and the Control Group for kinematics and kinetics during the task were found (when not wearing the sleeve).Our previous report of immediate effects of wearing a knee sleeve showed increased knee flexion at initial contact and peak flexion during stance during the step-down hop but no significant changes for sagittal plane knee joint moments . We undeOur SPM results do not support our hypotheses of lower vertical GRFs, and the discrete variable analysis does not support lower RFD for the (unsleeved) injured versus the uninjured sides for the group of 30 participants during the step-down hop. The SPM results also do not support the hypothesis that when wearing the sleeve, the peak vertical GRFs and RFD of the injured side increase significantly. However, based on the discrete variable analysis, a potential effect on RFD when wearing the sleeve may exist, although the post-hoc analyses did not reach significance.Our finding of lack of immediate differences for GRF in the three planes between the injured and uninjured sides with the SPM analysis, as well as between the sleeved and unsleeved conditions contrast with previous studies that found lower vertical GRF for the ACL-reconstructed sides , 21. ThuFy Anterior , combined with the shorter stance duration [Lower vertical GRF following ACL reconstruction may indicate a more cautious, hesitant landing pattern. Thus, the directional differences for the two groups for vertical GRF over the 6-week period may be of interest. The Sleeve Group had reported higher physical activity levels and duration during the 6-week period than the Control Group [duration  may reflFz (first and second peak during the stance phase). The (unsleeved) injured side had significantly lower peak eccentric and concentric power compared to the uninjured side. Particularly during the initial 5% of stance, the unsleeved injured side had a mean concentric (negative) joint power, suggesting a greater and slightly longer lasting  extension moment paired with a lower magnitude  angular velocity. In contrast, the uninjured sides had a mean eccentric (positive) power during that early stance phase as the flexion moment was initiated earlier. When wearing the sleeve, joint power increased during the first 5% stance for the injured side, becoming ‘more positive’, leading to similar values for the sleeved injured side and the unsleeved uninjured side. However, peak powers remained lower for the sleeved injured side compared to the uninjured side.The stance phase of landing includes the eccentric (absorption) phase and a concentric (propulsion) phase , 21. DurOur initial report suggested enhanced knee flexion angle at initial contact (mean difference 3°) when wearing the knee sleeve , alternaCombining that result with those of the current report with reference to the concentric power in the early stance phase, it is possible that the unsleeved ACL-injured knee lacks knee control during landing and decreased ability to absorb initial impact. That lack of control appears to be a short-lived extension moment and reduced angular velocity at initial contact, resulting in prolonged concentric knee power. The observed delayed flexion moment, more extended knee and reduced angular velocity at initial contact may also be explained by previously reported subtle increased quadriceps pre-activation prior to landing in a group ACL-reconstructed participants with similar duration post-surgery as our group . As outlBased on our findings, changes in knee power may explain possible immediate responses of enhanced landing knee flexion when wearing the knee sleeve, rather than adaptation or responses related to ground reaction forces. To confirm such hypothesis, knee angular velocity could also be explored. Findings for the 6-week intervention are less clear, mainly due to the small sample size. Wearing the sleeve regularly may lead to enhanced overall performance, evident in potential small increases for vertical GRF and shorter stance duration. Whether an increased vertical GRF explains the improved stance duration for the Sleeve group at follow-up, and implications of increased anterior GRF remain speculative considering the very low sample size. Increased anterior GRF at follow-up for the Control group poses the question whether they needed greater effort to hop at the same pre-defined, individualised distance as during the baseline assessment. Furthermore, compensatory responses of the hip, ankle and trunk and centre of mass positioning during landing need to be explored further.As a summary for the research pipeline, several directional changes are supportive of the sleeve’s role in improving function for individuals with ACL reconstruction. Immediate effects of wearing a knee sleeve included approximately 5% increased maximal single leg hop distance ; increasOur findings need to be interpreted with caution. Most variables that we explored had relatively large standard deviations compared to their means, suggesting large between-individual variability. We did not explore responses at the ankle, hip and trunk, which would add to the complexity of the analysis. Anticipation of a task (such as a drop jump) can lead to change in neuromechanical and functional differences in performance , 40, in a priori defined variables. However, time-aligning the respective peaks for each trial may mask potential differences between conditions and between participants. The discrete variable analysis of specified time points thus complemented the SPM analysis. As an explanatory study of findings, we performed multiple analyses, increasing the risk of Type 1 errors. On the other hand, as the COVID pandemic interfered with the follow-up sessions, only a small number of participants completed the RCT. The of Type II errors exists, thus those results, in particular, remain speculative.A strength of our analysis is that we included SPM as well as discrete variable analysis. SPM allows identification of differences across time series without Various confounders influencing the outcomes need to be considered. Wearing the knee sleeve may lead to improved knee-related confidence, or being prescribed a knee sleeve might lead to greater motivation to exercise or undertake physical activity, thereby potentially improving sensori-motor control and skill. The level of activity may influence outcomes such that those with higher performance levels may respond to a lesser degree to those with low performance (or greater impairment). We did not control for level of activity in the analysis, such as by the Tegner Activity scale. That remains a direction for future research with a larger sample. Lastly, time since surgery and sex influences biomechanical outcomes. We included participants with a large range of duration since surgery (6 months to 5 years), which may have confounded our results. We controlled for those two confounders by entering them as co-variates in the repeated measures ANOVAs of the discrete variable analyses. Thus, time since surgery and sex are unlikely to influence our findings.Mean knee power increased immediately during the first 5% of stance during a step-down hop when wearing the knee sleeve on the anterior cruciate ligament reconstructed (injured) side compared to not wearing the sleeve while peak powers did not change. The statistical parametric mapping showed no differences for ground reaction forces during this task when comparing the injured to the uninjured side, nor between the sleeved and the unsleeved condition for the injured side. Discrete variable analysis showed lower peak anterior ground reaction force for the injured versus uninjured sides. Based on the statistical parametric mapping and the discrete variable analysis, wearing the knee sleeve at least one hour daily for 6-weeks lead to a directional change of increased vertical ground reaction forces for the Sleeve Group at follow-up. Results of the 6-week follow-up need to be considered with caution due to the small sample size for those analyses.


These polymer-iodine materials are active against a broad range of microorganisms, including bacteria and fungi. It is suggested that the ease of manufacture and subsequent commercialization make said systems especially suited for applications as base materials for medical devices to reduce infection risks and control the spread of pathogens.Iodine-containing systems show broad antiseptic properties that can be an invaluable tool in controlling infections in humans and animals. Here, we describe the first proof-of-concept studies on biocidal active polyamide- and polyurethane-iodine complexes that are produced IMPORTANCE Infectious diseases are of mounting medical and public concern. A major contributor to this trend is the proliferation of medical implants, which are inherently vulnerable to microbial contamination and the subsequent onset of hospital-acquired infections. Moreover, implant-associated infections in humans are often difficult to diagnose and treat and are associated with substantial health care costs. Here, we present the development of biocidal active polyamide- and polyurethane-iodine complexes that are generated in situ during fabrication. We show that the excellent antiseptic properties of water-soluble povidone-iodine can be similarly realized in water-insoluble engineering plastics, specifically polyamide- and polyurethane-iodine. These complexes have inherent biocidal activity against major pathogenic bacteria and fungi. Health care-acquired infections (HAIs) continue to be a source of countless unneeded deaths and excessive hospital costs. The main sources of HAIs are pathogenic microorganisms that have entered the body due to contamination and infection or to imbalances in the normal microbiota  as a consequence of specific treatment conditions or weakened immune defenses. Often, an HAI forms at the site of a medical device , which causes the introduction of unwanted microorganisms at a specific body site or becomes the scaffold for unwanted adhesion of bacteria already carried by the patient. In fact, medical devices are a significant source of HAIs and represent a serious concern in many clinical settings –3. Micro–Staphylococcus aureus (MRSA) and mycobacteria  systems with biocidal activity, such systems are generally limited by two main issues: (i) the iodine source is PVP-I and/or (ii) the actual iodine complexation is not commercially viable. PVP-I is commercially available as a dry powder, of which the available iodine content represents about 10%. The use of PVP-I has two main disadvantages: (i) the addition of the desired amount of iodine will require a 9-fold addition of PVP to the system, and (ii) the PVP must not have a detrimental effect on the resultant product. PVP is a water-soluble, hydrophilic polymer, and substantial incorporation of said PVP product into a water-insoluble polymer matrix will have significant effects on the resultant product properties. One previous publication showed that the conjugation of PVP-I with cross-linked polystyrene resin could be used for bacterial decontamination of water, but in such cases, the PVP-I serves as a functional polymer rather than part of the fundamental engineering plastic matrix . There ain situ generation of iodine-polymer complexes during regular production steps is feasible and greatly increases the practicality of the production systems. In brief, for the thermoplastic polyamide and polyurethane systems, iodine complexation was conducted in the “melt” via hot melt extrusion techniques. For the thermoset polyurethane systems, iodine complexation was conducted in the melt during the actual polymerization of monomers and additives. The synthesis of thermosets  of polyurethane-iodine foams was subsequently increased to industrial scale to further demonstrate their application potential. Altogether, our study shows that the described polymer-iodine complexes can be simply produced by integrating the complexation step into existing process steps already employed for the base polymer materials. Thus, both the equipment and time needed to produce the polymer-iodine systems are similar to those needed for the base polymer processing, making these systems uniquely positioned for commercial scale-up. The resultant polyamide-iodine (PA-I) and polyurethane-iodine (PU-I) complexes show strong bactericidal and fungicidal activity.Our present study reports the fabrication of iodine complexes of two medically relevant polymer families, specifically polyamides (PA) and polyurethanes (PU). The biocidal properties of the resultant fibers and foams are demonstrated for some of the most commonly encountered and clinically relevant microorganisms. Importantly, we also provide proof of principle that PA-I and PU-I thermoplastic complexes were produced by direct extrusion of the base PA and PU polymers with a suitable iodine source in a twin-screw extruder. The extrusion conditions were dependent on the base PA and PU used and the ease of dissolving the iodine source into the molten PA matrix to generate the PA-I and PU-I complexes. The general extrusion temperatures were in the 150 to 240°C range, resulting in molten extrudates having stable melt viscosities and a transparent appearance. The final PA-I and PU-I cooled extrudates showed no surface defects, possessed undetectable vapor pressure from free iodine, and showed no iodine discoloration over extended time periods . Based on these observations, the incorporation and subsequent complexation of iodine with the PA and PU matrixes were deemed homogeneous and stable.The PU-I thermosets were produced by first dissolving the suitable iodine source in one of the raw materials for PU fabrication, primarily the polyol or diol raw material. The PU reaction was then conducted as usual to produce the PU-I thermoset. In this case, homogeneous PU reactions in the melt will only occur if the reactive ingredients are mixed and reacted on the molecular level to initiate the polyurethane reaction. Thus, it can be concluded that the iodine used and complexed in these reactive PU systems must also be incorporated homogeneously on the molecular level throughout the final PU-I matrix. The resultant PU-I thermoset systems showed no iodine vapor pressure and no iodine discoloration over time. The only noticeable effect of the iodine on the PU polymerization reaction was the inhibition of the PU reaction. However, this could be overcome by slightly tweaking and optimizing the PU process by utilizing more reactive raw materials  or by adding a catalyst. Iodine sources used for the complexation reactions included elemental iodine, and PVP-I . The resS. aureus  SH1000, S. aureus USA300 (MRSA), Streptococcus pyogenes, Staphylococcus epidermidis ATCC 35984, Candida albicans ATCC 10231, and Aspergillus fumigatus 293 , the formation of halos reflecting growth inhibition was still observed upon autoclaving   . This obin situ generation of the iodine complex during the actual polymerization reaction is a unique observation for this study. The in situ process to produce PU-I thermosets seems to be generic to polyurethane systems in general, and thus, it is expected that a broad range of PU-I systems can be produced simply and economically. The inhibitory effects on microbial growth of lab-produced foams composed of different formulations  or nonreticulated (closed cell). Accordingly, the capillary effects of liquid can have differential effects on the observed inhibitory zones. This observation implies that the compositional makeup of the PU foam with respect to wetting can also have indirect effects on the biocidal activity. This parameter should be considered in medical device design.Based on the positive results from various lab-produced PU-I foams, new development foams, both reticulated and nonreticulated, were produced at pilot-relevant scale , the resultant polymer-iodine blend obtained via hot melt extrusion was not stable, resulting in an iodine vapor pressure that immediately caused discoloration of adjacent materials. Our results thus provide proof of principle that PA-I and PU-I complexes can be produced that are commercially viable and show broad biocidal activity. The antiseptic attributes of PVP-I were successfully integrated into two commonly used biomaterial families, polyamides and polyurethanes, by the complexation with iodine. We also showed that the level of iodine concentration or the incorporation of other ingredients in the systems can have a significant effect on the growth inhibitory zones in our plate assays, suggesting that the polymer-iodine systems can be further customized to meet specific requirements for a particular medical need. Moreover, we showed that the biocidal properties of the polymer-iodine complexes included in this study are largely maintained upon sterilization, which strongly supports the view that the materials can be reused or will maintain their biocidal activity for an extended period of use. Thus, these polymers have the extra advantage of a low environmental footprint, since they can be recycled or allowed to remain in use for longer periods of time.In the case of PU-I foams, we show that the technology is readily scalable and that commercial production of both nonreticulated (closed-cell) and reticulated (open-cell) foams with biocidal activity is viable. The present research shows that the biocidal activity observed in the nonreticulated PU-I foam is maintained after reticulation. Finally, we developed a prototype face mask with a commercially produced PU-I reticulated foam that shows strong biocidal activity against oral bacterial flora. Reticulated PU foams are presently used as air-filtering media in a number of applications . The production of similar filtering media using reticulated PU-I foams could be beneficial to control the growth and spread of pathogens, especially for systems used in high-moisture applications, such as air conditioning and masks.In conclusion, the beneficial antimicrobial attributes of water-soluble PVP-I can be similarly realized in PA-I and PU-I materials. The production process for the PA-I and PU-I systems is simple, and the iodine complexation step can be integrated into existing process steps, which greatly improves their commercial viability. Both PA and PU materials show excellent biocompatibility and thus are used for the fabrication of a broad range of medical devices. Though this initial proof-of-concept study focuses mainly on the biocidal properties and potential commercial viability of PA-I and PU-I complexed materials, the ability to introduce desirable biocidal attributes through the complexation of iodine should be a strong justification for further development of these materials.Thermoplastic PA and PU systems (samples 1 to 23) were prepared via hot melt extrusion, using a Thermo Prism EuroLab 16 twin screw extruder having a 16-mm screw diameter and a 25-cm barrel length. The extruding barrel had five heating zones that were set in the range of 150 to 240°C, depending on the system being compounded. The rotation speed of the screws was fixed at 400 rpm. The powders/solids were initially dry mixed and then fed into the extruder. The extruded filament was water cooled and cut to length to produce the fibers. The following materials were used: polyamide 6 , polyamide 6 , polyvinylpyrrolidone K30 , polyvinylpyrrolidone-iodine , polyamide 11 , polyamide 12 , aliphatic polyether thermoplastic PU , and elemental iodine 99.8% (Sigma Aldrich/Merck).Thermoset PU systems (samples 24 to 38) were prepared by the reaction of an isocyanate with a polyethylene glycol/glycerol polyol blend, with or without an iodine source. If an iodine source was used in the reaction, the iodine was initially dissolved in the polyol blend prior to conducting the polyurethane reaction. Polyurethane reactions including an iodine source required the addition of a catalyst (DABCO) to accelerate the reaction. The polyurethane reaction was conducted by reacting the isocyanate with the polyol source at room temperature until homogeneous, and the reaction mixture was then poured into molds and placed in a 60°C oven for 2 h. The following materials were used: hexamethylene diisocyanate , toluene diisocyanate , polyethylene glycol 400 , glycerol (Sigma Aldrich/Merck), polyvinylpyrrolidone K17 (PVP K17), and 1,4-diazabicyclo[2.2.2]octane .Thermoset PU systems (samples 39 to 44) were kindly prepared by Caligen Europe BV. The PU systems were based on commercial processes and raw materials and supplied in their corresponding nonreticulated and reticulated forms. The reticulation process was conducted by combustion. Sample 39 was a commercial reticulated foam containing no iodine . Samples 40 to 43 were lab samples based on MDI (methylene diphenyl diisocyanate)/polyether polyol/polyester polyol/iodine foams that were produced at the kilogram scale. Sample 44 was a reticulated foam based on MDI/polyether polyol/polyester polyol/iodine commercially produced at a batch size of 1,500 kg. The resultant commercial PU foam bricks were then reticulated and finally peeled to give the final foam, having desired thicknesses of 1.5 to 3 mm.All subsequent biological experiments with the developed PA- and PU-based materials were replicated at least twice.Staphylococcus aureus (MSSA) SH1000, methicillin-resistant S. aureus (MRSA) USA300, a clinical Streptococcus pyogenes isolate, S. epidermidis ATCC 35984, Candida albicans ATCC 10231, and Aspergillus fumigatus 293 were grown in tryptic soy broth (TSB) overnight at 37°C. Aliquots (100 μL) of the overnight cultures were diluted to an optical density at 600 nm (OD600) of 0.1 and subsequently plated onto 100 mm Mueller-Hinton agar (MHA) plates. Fibers or foams with different concentrations of nylon, PVP, and iodine were placed on top of the plates, and the plates were then incubated at 37°C. Growth inhibition was inspected upon 24 and 48 h of incubation.Methicillin-susceptible 2O, dried, and autoclaved at 121°C .To evaluate a possible decrease in the microbial growth inhibitory efficacy of the investigated materials after standard sterilization by autoclaving, the fibers were washed once with 70% ethanol, rinsed with distilled HTo evaluate the effects of PVP-I on oral microorganisms, saliva samples from healthy volunteers were pooled and mixed to homogeneity using a vortex mixer. Subsequently, 1-mL aliquots of the pooled saliva were incubated with various foams  and without iodine (sample 39) to evaluate the activity of these foam materials on microorganisms commonly transmitted from the face and breath to face masks. Mouth masks were worn for 3 h by volunteers. Afterwards, the inside of the mask was gently pressed for 10 s onto BA plates. The plates were subsequently incubated for 24 h at 37°C. After pressing the inside and outside of the mask onto BA plates, a piece of the mask was cut and incubated on top of a BA plate at 37°C for 24 h.Studies with healthy volunteers wearing PU-I foam face masks were performed based on written informed consent with approval of the Medical Ethics Review Board of the University Medical Center Groningen  and with adherence to the Helsinki Guidelines.All data and materials are available upon request.


Mobile electrocardiogram (ECG) devices are valuable tools for teaching ECG interpretation. The primary purpose of this follow-up study was to determine if an ECG active learning session could be safely and effectively performed during the coronavirus disease 2019 (COVID-19) pandemic using a newly developed mobile 6-lead ECG device. Additionally, we examined the educational impact of these active learning sessions on student knowledge of cardiovascular physiology and the utility of the mobile 6-lead ECG device in a classroom setting. In this study, first-year medical students (MS1) performed four active learning activities using the new mobile 6-lead ECG device. Data were collected from 42 MS1s through a quantitative survey administered in September 2020. Overall, students felt the activity enhanced their understanding of the course material and that the activity was performed safely and in compliance with local COVID-19 guidelines. These results emphasize student preference for hands-on, small group learning activities in spite of the pandemic. The electrocardiogram (ECG) is a widely used diagnostic tool in medicine, and accurately interpreting ECGs is a critical skill that medical students must master. Graduating medical students are not adequately prepared to accurately assess ECGs in the clinical setting, and residents in specialties that frequently review ECGs often fail to recognize pathologic rhythms ,2. The ADue to the coronavirus disease 2019 (COVID-19) pandemic, university guidelines restricted most face-to-face learning activities, excepting tactile-learning activities ,5. In-peThis study aimed to assess students’ knowledge of cardiovascular physiology following the implementation of an active learning session using the new 6-lead ECG device. We hypothesized that the active learning session could be safely performed in person during the pandemic, would improve the teaching of cardiovascular physiology concepts, and increase familiarity with telemedicine-enabled ECG devices.This study was qualified as exempt research by the University of California, Irvine, Institutional Review Board for Human Subjects. Responses to survey questions were anonymous, shared in aggregate form, and maintained privacy and confidentiality.We report an observational study based on a questionnaire survey after subjects had completed the active learning session. Reporting was consistent with the STROBE  statement .This study was performed at the University of California, Irvine, School of Medicine in September 2020. There was no follow-up study. After completion of the active learning session, students were asked to complete an optional, anonymous survey via Qualtrics to understand participant perception of the ECG activity.Prior to the active learning session, students were informed that the activity involved recording, interpretating, and sharing ECG readings with their fellow group members. Student participation was entirely optional, and no student was required to record and share their ECG reading with the group. Informed consent was obtained via Qualtrics survey for each participant. Faculty members and second-year medical students were available to review student ECG strips and advise further evaluation by a physician should any cardiovascular abnormality be detected during the active learning activity.KardiaMobile 6L devices and Apple iPads were provided to each student group . InstrucThe active learning session took place in two lecture halls to abide by social distancing practices. The activity was split over two 50-minute periods to allow for smaller groups of approximately 25 students per session. Preestablished clinical learning groups were maintained to minimize new and unnecessary contact between participants. KardiaMobile ECG devices were cleaned with alcohol wipes between uses, and students were encouraged to use hand sanitizer before and after the active learning session. Within the lecture hall, small groups were physically distanced at least 6 feet (1.8288 m) apart and universal masking was enforced. Before the in-person session, students with a fever, cough, or any other COVID-19 symptoms were asked to self-triage and remain at home.Eligibility criteria included enrollment in the 1st-year medical physiology and pathophysiology course at the University of California, Irvine, School of Medicine. Exclusion criteria included students who had previously completed ECG training with different devices. Out of 49 target subjects, 46 students participated in the active learning session and survey.All 9 questionnaire items on knowledge, skills, and pandemic safety were variables following the 6-lead mobile ECG active learning session.We developed the 9 item, 4-point Likert scale survey instrument  to evaluStudents self-selected to attend the active learning session and complete the post-activity survey were not assigned or chosen.The study size was not estimated because whole target students were recruited.Descriptive statistics were used for the data analysis.Demographic data were not collected.Student responses to the post-activity survey indicated that the majority of students had limited experiences with mobile medical devices before starting medical school , Q1. FurRegarding student responses to holding an in-person active learning session during the height of the 2020 COVID-19 pandemic, 98% of students agreed or strongly agreed that they felt comfortable attending the “Reading ECG” session. They also felt that the “Reading ECG” session was operated in a manner that complied with current University COVID-19 guidance , Q6, Q7.This follow-up study expands on the initial pilot study , using tActive and experiential learning increases student engagement and competency , and theFuture directions for research in this area include incorporating the KardiaMobile device into remote ECG teaching modules during clinical rotations to emphasize basic pathophysiological concepts and to create a longitudinal learning experience between the 1st through 3rd years of medical school.This study focuses on the interpretation of non-pathologic sinus rhythms, resulting in limited experience in reading abnormal ECG findings. In addition, we are not sharing a direct comparison to the single-lead KardiaMobile ECG device, so we cannot make any claims regarding if the 6-lead device provides a superior educational experience.The active learning with the 6-lead KardiaMobile ECG device is a valuable addition to physiology education for medical students. This study emphasizes student preference for hands-on, small group learning activities, particularly during social and educational isolation periods. Also, the hypothesis that the active learning session could be safely performed in person during the pandemic could be accepted.


The aim of the study was to develop the Brazilian version of the Oral HealthImpact Profile - Aesthetic Questionnaire (OHIP-Aes-Braz) and test itspsychometric properties. The questionnaire test versions were developed by apanel of experts and a pre-test was conducted in a focus group. Data used fortesting its psychometric properties were obtained from a randomized controlledclinical trial on tooth bleaching. Seventy-nine Brazilian adults were included.The questionnaires were applied before tooth bleaching treatment (baseline), oneweek (T1), and one month after the intervention (T2). Reliability was assessedin terms of internal consistency and stability, while validity was ascertainedby criterion and construct validity. The sensitivity to change was assessedcomparing the total scores at baseline and T2, using the Wilcoxon test (α =0.05). Both stability and internal consistency  proved to be adequate. Construct validitywas confirmed as the correlation between OHIP-Aes-Braz scores with tooth colorsatisfaction and self-perceived oral health were in the expected direction. Apositive correlation between OHIP-Aes-Braz and OHIP-14 (rs=0.63) and OIDP(rs=0.77) was observed. The instrument was responsive once differences in totalscores before and after treatment were statistically significant (p<0.001).The OHIP-Aes-Braz presented good psychometric properties and showed sensitivityto change regarding aesthetics evaluation in Brazilian adults treated with toothbleaching. A valid and reliable instrument allows a suitable assessment of oralhealth-related quality of life in Brazilian patients submitted to aestheticsdental interventions. Theshift from the disease-centered concept of health  into amultidimensional theory led to the emergence of the construct health-related qualityof life (HRQoL). The understanding that oral health is also related to theindividuals’ physical, mental and psychosocial well-being denotes the importance oforal health in people’s quality of life Aesthetics represents a concept based on subjective perception and varies fromindividual to individual. Thus, dental aesthetic itself, as well as the results ofinterventions to improve it, are hard to evaluate, especially if aesthetics’assessment uses professional normative criteria but does not account for theindividual’s perspective ,,,Several instruments have been used to measure OHRQoL. The Oral Health Impact Profile(OHIP) is one of the most used for this purpose. Some authors have shown anassociation between dental aesthetics and OHRQoL, which makes OHIP suitable for thestudy of the impacts of aesthetic dental treatments ,,,,Cross-cultural validation of quality-of-life questionnaires are important so thatthey can be applied in locations and cultural contexts other than that where theywere developed, also allowing for comparison of results between countries anddifferent populations The aim of this paper was to develop the Portuguese version of OHIP-Aes, throughtranslation and cross-cultural adaptation, as well as to evaluate the psychometricproperties  of the instrument, in apopulation of Brazilian adults treated with tooth bleaching.The study was designed to validate the OHIP-Aes instrument in the Portugueseversion (OHIP-Aes-Braz), using a sample of patients undergoing tooth whiteningin a controlled, randomized, parallel and triple-blinded clinical trial,approved by the Research Ethics Committee (CAAE number 44564115.4.0000.5020) andregistered in the Brazilian Clinical Trials Registry (RBR-9mys6q). The clinicaltrial objective was to test the efficacy and tooth sensitivity to whiteningtreatment in adult patients who used desensitizing toothpaste, compared to thosewho used regular toothpaste. The dentifrice tubes were covered with an opaqueband marked with numbered codes to blind the participants to groupallocation.,The sample size was calculated considering that the study should have a 5%significance level and 80% power to detect a minimal difference of 3.5 in theoverall score of OHIP-Aes between the two treatment groups. Previous studies hadsuggested that this detectable difference should be at least 3 to 5 units A total of 79 adult individuals, aged 18 or over (range 18-39), of both sexesparticipated in the study; after being informed about the study objectives andprocedures they signed the informed consent forms and were enrolled. Eligibilitycriteria were individuals with the six maxillary anterior teeth free of caries,without restorations on the labial surfaces, with superior central incisorscolor shade A2 or darker . The exclusion criteria were individuals who reported previous anteriorteeth sensitivity or who presented anterior teeth with enamel cracks, exposeddentin, or severe internal discoloration , individuals with active periodontal disease, pregnant or lactating women,and patients using any anti-inflammatory, analgesics or antioxidantmedicines.Participants answered OHIP-Aes questionnaire before being submitted to toothwhitening. The instrument was applied in duplicate at this stage, with aone-week interval between assessments . The questionnaire was self-administered,always under the supervision of a researcher, who was trained to help theparticipants to answer the questionnaire with standardized explanations, whenasked to. Tooth whitening was performed in two sessions with the in-officetechnique, using 35% hydrogen peroxide  in three 15-minute applications persession, with an interval of one week between sessions, following themanufacturer’ recommendations.The color evaluation was performed using a Vita classical  value-oriented shade guide, by two calibrated operators whowere blinded to the allocation assignment. The data was registered at thebeginning (time 0) and one month (time 2) after the intervention. A variation ofVita Classical units between both times , one week (time 1) and one month (time 2) after the intervention.A flowchart of the translation and cross-cultural adaptation steps and thepsychometric properties evaluation of the Portuguese version of OHIP-Aes ispresented in The OHIP-Aes instrument was originally developed and validated in the Englishlanguage and derived from OHIP-49 items ,,,For each of the 14 questions from OHIP-Aes, patients are asked how often theyexperienced the impact “in the past two weeks”. The original OHIP-49investigates impacts in the last six months. This change was proposed and testedin a previous study, in order to be sensitive to changes in OHRQoL of patientsundergoing tooth whitening and proved to be adequate For the development of the Portuguese version of OHIP-Aes, the originalinstrument developed in English language At the end of this stage, the group of experts concluded that some items ofOHIP-Aes in English differed from the items that they considered appropriate forthe Brazilian culture. Therefore, two versions of the instrument were tested.The first version (named OHIP-Aes-V1) consisted of thetranslation-back-translation of the 14 items enclosed in the originalinstrument, published in English. The second version (named OHIP-Aes-V2)consisted of 11 questions translated from the original instrument plus threequestions suggested by the panel of experts to be tested as substitutes forquestions 1, 2, and 9 of OHIP-Aes-V1. They were chosen from the 49-item originalinstrument version A pre-test of the questionnaire preliminary version was carried out with a groupof individuals with sociodemographic characteristics similar to those who wouldbe part of the main study (young adults of both sexes and who had completedelementary school). Individual interviews followed by a focus group wereconducted After the pre-test stage, the changes or adaptations suggested in the wording ofitems were re-evaluated by the panel of experts at the final review of theinstrument. An expert in the English language judged whether the suggestedchanges would help the comprehension of the instrument in the Portugueselanguage without changing the meaning of the item in the English language.The reliability of both versions (OHIP-Aes-V1 and OHIP-Aes-V2) was assessed bytheir stability and internal consistency. The internal consistency wasdetermined by the correlation between different items that compose theinstrument and the degree of scale homogeneity. The results of the instrumentapplied at time 0.1 were analyzed for inter-item correlation and totalitem-score correlation (item-rest), using Cronbach's alpha coefficient. Afterthat, a final version of the instrument, derived from the tested items thatpresented better internal consistency, was used for subsequent tests. Thisversion was named OHIP-Aes-Braz.According to the test-retest model, the OHIP-Aes-Braz instrument stability wasdetermined applying the instrument twice to the same individual, in a timeinterval in which there was no change in the individual’s state concerning thedental aesthetics. Therefore, the group of 79 individuals seeking bleachingtreatment answered the questionnaire at the beginning of the study (baseline).After one week (time 0.1), without any therapeutic intervention or any change inthe dental aesthetics, 77 individuals answered the questionnaire again. Theagreement of the scores obtained in both moments was evaluated using theintraclass correlation coefficient (ICC).The validity of OHIP-Aes-Braz, that is, its ability to detect impacts of dentalaesthetics on individuals’ quality of life, was assessed by the associationbetween the total score of the instrument and clinical and subjective parametersrelated to dental aesthetics, both measured at baseline (time 0).The convergent construct validity was evaluated by the correlation between thetotal score of the instrument and the aesthetic self-perception single itemquestion. The question used was: “How much are you satisfied with the color ofyour teeth?”. The responses were recorded in a five-point Likert scale: ‘verydissatisfied’ The concurrent criterion validity was assessed by the correlation between thetotal scores of OHIP-Aes-Braz and the total scores of the validated Brazilianversions of the instruments OHIP-14  The OHIP-Aes-Braz discriminatory ability was analyzed by comparing thedifferences between the total scores after tooth whitening in patients with andwithout reported sensitivity one week post-treatment (time 1), and indissatisfied/neutral patients and patients satisfied with the color of theirteeth one month after treatment (time 2). The Wilcoxon test was used.The OHIP-Aes-Braz responsiveness, that is, its ability to detect changes overtime resulting from the intervention, was assessed by sensitivity to change inthe construct in patients undergoing tooth whitening. The OHIP-Aes-Brazinstrument sensitivity in detecting these changes was evaluated by thedifference between the total scores before (time 0) and after treatment (time2).The responsiveness of OHIP-Aes-Braz was also compared to the changes detectedusing OHIP-14 and OIDP, through the correlation of the differences between thefinal and initial scores of the instruments , was used for all analyzes, adopting a 5% significance level.One hundred twenty-one patients were examined for eligibility. Seventy-nine patientswere included in the randomized clinical trial. The sociodemographic characteristicsof the study population were as follows: 63.3% were female, the mean age was 24.4 +5.0 years old, the marital status was single for 83.5%, the mean years of schoolingwas 15.3 + 1.7, and 64.6% had monthly family income of more than five Brazilianminimum wages (1BMW=US$ 193.00 at the study time). Sixty-seven patients wereevaluated at the end of follow-up (time 2), considering losses to follow-up (n=11)and one patient who did not receive the intervention for declining to participateafter inclusion in the study.Although Cronbach's alpha coefficient was high for both versions, items 1 and 2of the OHIP-Aes-V1 version and item 9 of the OHIP-Aes-V2 version contributed toa better internal consistency, that is, a better correlation between items andthe total score.Thus, the final tested version included the 13 questions translated from theoriginal instrument The OHIP-Aes-Braz instrument showed convergent construct validity since thebaseline total scores presented a significant negative correlation with colorsatisfaction and self-perception of oral health, as expected . IndividWhen evaluating the concurrent criterion validity through the correlation betweenthe OHIP-Aes-Braz and OHIP-14 and OIDP total scores, it was observed that therewere significant positive correlations between the instruments. The greater theimpact measured by OHIP-Aes-Braz, the greater the impact measured by OHIP-14 andOIDP .When comparing the difference in post-whitening total scores indissatisfied/neutral patients and patients satisfied with tooth color at the endof treatment, OHIP-Aes-Braz was able to discriminate these groups of patients.The ability of OHIP-Aes-Braz to discriminate individuals with and without toothsensitivity was assessed at the immediate postoperative follow-up . At this time, the postoperativesensitivity was still elevated. The mean total score of the instrument inpatients without sensitivity (2.93 ± 4.8) was lower than in patients withsensitivity (4.13 ± 6.0); however, this difference was not statisticallysignificant . It is worth mentioning that 30 daysafter the end of the treatment no individuals reported tooth sensitivity (datanot shown).There was a significant difference in OHIP-Aes-Braz total scores between times 0and 2  and also between times 1 and 2  ,demonstrs=0.01, p=0.94) and OIDP , it was observed that only the variation in theOHIP-Aes total score was statistically significant . It means that OHIP-Aes-Braz was responsive toclinical outcomes related to the dental aesthetics, that is, the bleached teethcolor, whereas OIDP and OHIP-14 were not.When comparing the OHIP-Aes-Braz responsiveness to the changes regarding theclinical difference in the upper central incisors color using OHIP-14. Although an internal consistency greater than 0.70 is consideredsatisfactory for comparisons between groups When assessing instrument’s homogeneity, moderate correlations between items aredesirable; high correlations may reveal redundancy and low correlations imply thatthey do not offer a relevant contribution to the scale. Items 3 (sensitivity to coldand hot foods) and 4  showed values of correlation with thetotal scale score below 0.20, which might suggest that they could be deleted since,according to Streiner and Norman The OHIP-Aes-Braz instrument items assess more than one construct dimension so thatweak correlations between items and the total score may occur. In the present study,both items that showed a lower correlation with the scale total score belong to the“physical pain” domain. A plausible explanation would be the sample’s socioeconomiccharacterization, which could probably justify a greater use of dental services andthe absence of pain and sensitivity before clinical intervention . On the other hand, aestheticinterventions can cause transient postoperative sensitivity or pain, such aspost-bleaching sensitivity, so that these individuals’ quality of life can bemodulated for better or worse depending on the balance between aesthetic improvementand side effects of treatment In addition to presenting excellent stability and internal consistency, theOHIP-Aes-Braz instrument showed construct and criterion validity. There was asignificant negative correlation between OHIP-Aes-Braz and satisfaction with toothcolor, as well as with individuals’ self-perceived oral health. It means thatindividuals less satisfied with their tooth color had a greater negative impact onOHRQoL and those with better self-perceived oral health had a lesser negative impacton their quality of life. For criterion validity, OHIP-Aes-Braz measurements were inthe same direction as the other instruments tested, OIDP and OHIP-14.,The OHIP-Aes-Braz was also able to discriminate satisfied patients from those notsatisfied with tooth color at the post-treatment, similar to versions in otherlanguages It is expected that once the tooth whitening effect persists, patients will continueto experience positive psychological, social and functional impacts It is important to clarify that this study was primarily designed to test theefficacy of dental bleaching on a sample of adults living in a Brazilian city. Thesample consisted mostly of young individuals who sought an exclusively aesthetictreatment, with family income above five minimum wages and who had attended anaverage of 15 years of study. It should not be considered a representative sample ofthe Brazilian population. Then, the generalization of our results must be made withcaution; testing the instrument before using it in other settings is recommended.Furthermore, other aspects deserve to be pointed out as possible limitations of thestudy. There was a dropout rate of 15% which could have resulted in selection bias.However, the characteristics related to sociodemographic and clinical and subjectivemeasures were similar between those who discontinued and those who were followeduntil the end of the study. In addition, the study power was not compromised, sinceit was within the rate calculated at the beginning of the study, satisfying theminimum sample of patients.Another relevant issue is that the color change was the main clinical aspectinvestigated. Although tooth color is one of the main characteristics concerningdental aesthetics, it would be suitable to test this instrument in otherinterventions intended to modify other important aspects of dental aesthetic, suchas the size, shape, and position of teeth The Portuguese version of the OHIP-Aes instrument, OHIP-Aes-Braz, which was adaptedand tested in this study showed reliability, in terms of internal consistency andstability. It also proved to be valid, discriminatory, and responsive, beingsensitive to the change in the perception of OHRQoL in adults submitted to toothbleaching.


Humoral immunity after SARS-CoV-2 vaccination has been extensively investigated in blood. Aim of this study was to develop an ELISA method in order to determine the prevalence of IgG and IgA SARS-CoV-2 domain 1 spike-protein (S) specific antibodies (Abs) in buccal and nasal mucosal surfaces of vaccinees.To this end, we analyzed 69 individuals who received their first vaccine dose between February and July 2021. Vaccines administered were BNT162b2, mRNA-1273 or ChAdOx1-nCoV-19. Detection of IgG and IgA Abs was performed using commercial ELISA kits for both blood and swab samples after protocol modification for the latter.Anti-spike IgG and IgA Abs in the buccal and/or nasal swabs were detectable in >81% of the study subjects after the second dose. The IgG measurements in buccal swabs appeared to correlate in a more consistent way with the respective measurements in blood with a correlation coefficient of r=0.74. It is of note that IgA Abs appeared to be significantly more prevalent in the nasal compared to the buccal mucosa. Optimal selection of the assay cut-off for the IgG antibody detection in buccal swabs conferred a sensitivity of 91.8% and a specificity of 100%. Last, individuals vaccinated with mRNA-based vaccines exhibited higher antibody levels in both blood and mucosal surfaces compared to those receiving ChAdOx1-nCoV-19 confirming previously reported results.In conclusion, our findings show a differential prevalence of anti-S Abs on mucosal surfaces after vaccination for SARS-CoV-2, while they also set the basis for potential future use of IgG antibody detection in buccal swabs for extended immunity screening in large populations. The emergence of SARS-CoV-2 has challenged the world during the last two and a half years in an unprecedented scale with more than 528,000,000 confirmed recorded cases and more than 6,000,000 deaths . BetweenFor this observational cohort study we recruited and analyzed 69 adult individuals who underwent a full SARS-CoV-2 vaccination with BNT162b2, mRNA-1273, ChAdOx1-nCoV-19 or combination between February and July 2021. Blood and swab samples  were collected before and after each vaccination dose in order to determine the prevalence of IgG and IgA anti-S Abs in both serum and mucosal surfaces. The clinical protocol for sample and data collection along with the informed written consent were approved by the Institutional Review Board at Ulm University (No. 488/20).Severe immunodeficiency, pregnancy and intake of glucocorticosteroids were predefined as exclusion criteria. All participants were older than 18 years and were eligible to receive vaccination against SARS-CoV-2. The administered vaccination schemes adhered to the then in force recommendations of the German Standing Committee on Vaccination (STIKO) and as previously described .The blood and swab samples were collected up to one week before or on day of first vaccination, two to four weeks after first vaccine dose depending on vaccination scheme  and one to four weeks after second vaccine dose. Sample collection was continued on a three-month interval basis after second vaccine dose up to one year after first vaccination dose. These measurements were, however, not included in this analysis due to the emergence of multiple vaccination schemes with respect to the booster vaccine doses administered. The blood samples were collected in two 5 ml or one 8 ml container with gel separator. After centrifugation at 3000 rpm for 10-15 minutes, serum was efficiently separated from the rest blood components at the upper compartment of the container. The swab samples were self-collected by the participants after sufficient training and supervision of trained personnel. Swabs with flocking technology on tips (i.e. flocked swabs) from Copan Italia S.p.A. were used for sample collection in mouth and nose as this kind of swabs have been shown to ensure better sample yield and more efficient release of sample into liquid media compared to non-flocked swabs .Following clinical data were recorded throughout the study: age, sex, date and type of vaccine administered, previous or breakthrough infection with SARS-CoV-2 confirmed by nucleic acid amplification test (NAAT) with additional information on diagnosis date and disease course as well as prevalence and intensity of side-effects after vaccination. The latter were categorized according to intensity as non-existing, mild or moderate. No severe side-effects that would require hospitalization were observed in any of the participants. As mild were considered local reactions at injection spot or mild systemic reactions like for example mild fatigue and headache. As moderate were characterized reactions that required the intake of painkillers and/or significantly reduced the ability of the vaccinee to perform normal daily routine tasks for more than five consecutive hours.The IgG and IgA Abs against the S1 domain of the SARS-COV-2 spike (S) protein were detected in both serum and swab samples using the respective EUROIMMUN anti-SARS-CoV-2 ELISA assays . For serum samples the assay was performed according to manufacturer’s instructions and as previously described . OD ratiOD values for ELISA measurements were recorded as numerical continuous variables. Correlation coefficients between the measurements for IgG buccal swab, IgA buccal swab, IgG nasal swab, IgA mucosal swab and the respective measurement in the blood were determined and reported as Pearson correlation coefficient r. Scatterplots between these measurements were created and the respective regression line with 95% confidence interval as well as the regression formula and model diagnostics were added. For cutoff determination for the different measurements in nasal and buccal samples a receiver operating characteristic (ROC) analysis was performed given the result of the blood measurements as reference and the area under the curve (AUC) was computed. In the plots for antibody levels after first and second vaccination, median values with error bars are plotted for different immunization schemes and types of measurement. Statistical significance was set at p<0.05.Overall, 69 healthy adult individuals with a median age of 55 years (range 18-65y) were enrolled in the study. The majority of the subjects were female (76.8%). All participants received a full vaccination scheme according to the then current guidelines with BNT162b2, mRNA-1273, ChAdOx1-nCoV-19 or a combination of those. According to vaccination scheme (booster dose not included) the participants were categorized in overall seven groups. The majority received a double dose of BNT162b2 (44.9%), while all but 4 participants that initially received ChAdOx1-nCoV-19 were subsequently vaccinated with either BNT162b2 or mRNA-1273. Three subjects with positive COVID-19 anamnestic were only vaccinated once according to then applied guidelines. The intervals between first and second dose varied according to the vaccine administered, with 3 to 4 weeks being the standard interval for the mRNA vaccines and 6-12 weeks for ChAdOx1-nCoV-19. Data regarding side-effect profile of the various vaccination schemes, detectability of mucosal anti-S IgA and IgG Abs as well as information on booster dose and breakthrough infection are summarized in Although first vaccination dose was not able to induce a detectable mucosal humoral immunity in a significant number of participants - yet with marked differences observed between different vaccination groups see Table 1 One of the main objectives of this study was to establish a reliable and consistent method for IgG and IgA anti-S Ab detection in samples from buccal and nasal mucosal surfaces. To this end, OD ratios from buccal and nasal samples were compared with those from serum. Statistical analysis of these data yielded a relatively good correlation coefficient of r=0.74 for the IgG assay in buccal swabs. For nasal swabs correlation was inferior with an r=0.61. The IgA assay exhibited higher divergence and lower concordance, especially in nasal swab samples, for which the correlation coefficient was only 0.61. These results are graphically depicted in Given that the IgG assay in buccal swabs demonstrated the highest correlation with serum samples, we proceeded in establishing an adjusted cut-off in order to achieve best possible accuracy, which would render the assay suitable for qualitative immunity screening. Indeed, reduction of OD ratio cut-off from 1.1 to 0.2 for the IgG buccal swab assay led to a sensitivity of 91.8% and specificity of 100%. This calculation was based on overall 520 paired measurements. The result is also graphically presented in IgA anti-S Abs were markedly more prevalent in samples from the nasal compared to the buccal mucosa. It is of note, that in 69.5% of the participants IgA anti-S Abs were detectable in nasal swabs although the corresponding serum sample had an OD ratio under the cut-off. This finding could be indicative of either cross-reactive IgA Abs present on nasal mucosa or higher degree of contamination with blood in nasal swab samples compared to the buccal ones.Participants that were either vaccinated at least once with an mRNA vaccine or were convalescent for SARS-CoV-2 before first vaccination exhibited significantly higher mean IgG and IgA anti-S Abs OD ratios compared to their peers that received only ChAdOx1-nCoV-19. Further comparison between BNT162b2 only, mRNA-1273 only or combination of these two with ChAdOx1-nCoV-19 indicates a higher potency of mRNA-1273 to induce a robust humoral immunity systemically as well as at mucosal surfaces compared to BNT162b2. These results are depicted in the form of errorbar plots for IgG and IgA Abs mean OD ratio after first and second vaccination in via standard blood-assays can be both logistically and financially unaffordable when applied in large populations. Lately, an increasing number of studies focus on the development of Ab detection from mucosal samples  approved the study. The patients/participants provided their written informed consent to participate in this study.CT, BJ, HS, and DaF are principal investigators. They designed the study, performed data analysis/interpretation and wrote the manuscript. CL, JS, MP, JH performed ELISA testing; IR, SK, DoF, CN, and EA reviewed the data and edited the manuscript. All authors contributed to the article and approved the submitted version.This work received grant support from the Ministry for Science, Research and Arts of Baden-Württemberg, Germany, and the European Commission  to HS and from the German Red Cross Blood Transfusion Service Baden-Württemberg – Hessen to BJ.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Temporary closures of outpatient health facilities and transitions to virtual care during the COVID-19 pandemic interrupted the care of millions of patients with diabetes contributing to worsening psychosocial factors and enhanced difficulty in managing type 2 diabetes mellitus. We explored associations between COVID time period and self-reported diabetes distress on self-reported health among a sample of Alabama Medicaid-covered adults with diabetes pre-COVID (2017-2019) and during-COVID (2020-2021).In this cross-sectional study, we surveyed a population-based sample of adults with type 2 diabetes covered by the Alabama Medicaid Agency. Participants were dichotomized into pre-COVID (March 2017 to October 2019) vs during-COVID (October 2020 to May 2021) groups. Participants with missing data were removed from analyses. We assessed diabetes related stress by the Diabetes Distress Scale. We measured self-reported health using a single item with a 5-point Likert scale. We ran logistic regressions modeling COVID time period on self-reported poor health controlling for demographics, severity of diabetes, and diabetes distress.In this sample of 1822 individuals, median age was 54, 74.5% were female and 59.4% were Black. Compared to pre-COVID participants, participants surveyed during COVID were younger, more likely to be Black  and female . This group also had fewer individuals from rural areas , and shorter diabetes duration . During COVID individuals reported modestly lower levels of diabetes distress  when compared to the pre-COVID group. After adjusting for demographic differences, diabetes severity, and diabetes distress, participants responding during COVID had increased odds of reporting poor health .We found respondents were more likely to report poorer health during COVID compared to pre-COVID. These results suggest that increased outreach may be needed to address diabetes management for vulnerable groups, many of whom were already at high risk for poor outcomes prior to the pandemic. The coronavirus disease of 2019 (COVID-19) pandemic had extensive impact in the United States causing over 700,000 deaths and sparked new fears of economic turmoil and social isolation , refers to the southeastern region of the United States where prevalence of DM is disproportionately high (> 11%) as are rates of diabetes-related complications and mortality . NotablyEvidence also suggests that COVID protective measures may have had significant impact on individuals physical and mental health, with some populations experiencing higher rates of anxiety, depression, and perceived stress during the pandemic . MoreoveIn this study, we examined the relationship between diabetes distress, depressive symptoms, diabetes management self-efficacy, and perceived stress with self-reported health in Alabama Medicaid-covered adults with diabetes between COVID time periods (prior to vs during).We conducted a cross-sectional survey within the Alabama Care Plan study. Briefly, the Alabama Care Plan (ACP) was an observational study of the quality of care of adults with diabetes covered by Alabama Medicaid. The Alabama Care Plan study enrolled a population-based sample of adults with type 1 or 2 diabetes who were covered by Alabama Medicaid between March 2017 and May 2021. Medicaid eligibility for adults in Alabama includes parents of minor children with incomes at or below 18% of Federal Poverty Level (FPL) and adults with disability eligible for the Supplemental Security Income (SSI) program . As partThe current study examines survey responses before and during the COVID pandemic. Adults were eligible if they met the following criteria: age 19 to 64 years old, covered by Medicaid for the prior 12 months, and were diagnosed with diabetes, defined by the presence of at least one inpatient or two outpatient International Classification of Diseases (ICD-9 or ICD-10) diagnosis codes used by the CMS Chronic Conditions Warehouse project , in the Survey methods have been described previously . BrieflyMeasures (described below) included those that assessed self-reported health, depressive symptoms, perceived stress, diabetes management, and stress relating to diabetes with additional questions on socio-demographics. Participants during COVID completed additional questions relating to COVID experiences and access to care.The self-reported health survey is a single-item ordinal measure with 5 levels varying from excellent, very good, good, fair, or poor. This survey is a widely used indicator of general health status in epidemiologic and population health research and is often categorized into excellent, very good, or good versus fair or poor .The PHQ-8 is an 8-item survey used for assessing depression that incorporates DSM-IV depression criteria with other leading major depressive symptoms into a numerical score graded as mild (5-9), moderate (10-14), moderately severe (15-19), and severe depression (>20) .The PSS-4 is a 4-item survey used to measure perceived psychological stress relating to general stress in the previous month. Scores range from 0 to 16 with higher scores indicating greater perceived stress , 19.The PDSMS is an 8-item survey measuring diabetes self-efficacy, adapted from the Perceived Medical-Condition Self-Management Scale. Scores range from 8 to 40, with higher scores indicating more confidence in self-managing one’s diabetes. Higher scores are associated with higher reported self-care activities and better glycemic control .The DDS is a 17-item scale that evaluates distress relating to the emotional burden, physician-related distress, regimen-related distress, and interpersonal distress of managing type 2 diabetes over the past month. The mean score is graded on a possible score range of 1–6 with a score of less than 2 indicating low diabetes distress, 2 to greater than 3 moderate diabetes distress and ≥3 severe diabetes distress  were pulled from two sources and modified based on feedback from a community advisory board and/or to simplify administration over the phone , 22. Para priori based on established or potential relationship of the covariate with our outcome variable; or 2. Found to differ between the pre- vs. during-COVID groups. Model 1 adjusted for demographics, model 2 added disease severity factors to model 1 and model 3 added diabetes distress to model 2. We present results for model 3. We then compared experiences of individuals reporting poor and better health during COVID.For analysis, participants were dichotomized into pre-COVID (March 2017 to October 2019) vs during-COVID (October 2020 to May 2021) groups see Figure 1In this sample of 1,822 individuals Table 1,Participants during COVID were younger with higher proportion of Black individuals  and more females . The during COVID group had fewer individuals reporting inability to work ; fewer individuals from rural areas ; and a shorter diabetes duration . The during COVID group reported slightly higher perceived self-management ; moderately better stress ratings ; and modestly lower levels of diabetes distress  when compared to the pre-COVID group.After adjusting for demographic differences, diabetes severity, and diabetes distress, participants responding during COVID had increased odds of reporting poor or fair health  as seen in Participants during COVID who reported poor health were less likely to be working  compared to those with better health. This group was also less likely to be married . This group had higher PHQ-8 scores , lower PDSMS scores , higher PSS-4 scores , and higher DSS scores  as seen in via telehealth or phone visit with majority of this group completing a telephone visit. Within this group, 19.8% of participants reported a video visit. Participants who reported poor health were significantly more likely to believe they have had COVID-19 regardless of testing.Among participants surveyed during COVID, 34.8% of participants experienced an appointment cancellation or rescheduled appointment with majority due to doctor’s office canceling or moving appointment. Over half of participants were offered a virtual visit We found significant differences between the pre-COVID and during-COVID groups participants Table 1.Our survey questions related to healthcare experiences during COVID Table 4 Interestingly, participants who reported poor health were significantly more likely to believe they have had COVID regardless of testing. Additional studies may be needed to identify other contributors to poor self-reported health during COVID within this Alabama Medicaid population.This is a cross-sectional study; thus, we are unable to infer causation between COVID and poor self-reported health. A longitudinal survey with the same respondents at both time periods would help mitigate this limitation. Further, we cannot be sure that differences were not due to policy changes occurring within Medicaid itself or other seasonal changes that may have co-occurred temporally. Our study sample includes adults with type 2 diabetes covered by Alabama Medicaid, which limits the generalizability of our findings to other populations. We used single item measures to review self-reported health which does not fully reflect the multidimensionality or complexity of a participant’s health. Assessments of health were based on self-report, we were unable to include objective measures of diabetes control such as HbA1c. Additional limitations include the limited number of respondents in the during-COVID group and significant demographic differences between respondent groups.In this sample of Medicaid-covered adults with type 2 DM living in Alabama, individuals surveyed during-COVID reported poorer health compared to those surveyed pre-COVID. Within the during-COVID group, those reporting poor health were more likely to report worse psychosocial symptoms than those who reported better health. Further findings also suggest that while individuals reporting poor health and better health faced similar delays in care, those reporting poor health during-COVID were more likely to believe they have had COVID regardless of testing. Taken together, these findings suggest that physical and mental health may have worsened among some low-income individuals with type 2 DM. Outreach efforts should include specific screening for stress and depression in order to identify and support those in need.The datasets presented in this article are not readily available because of institutional restriction, the generated dataset is not publicly available. Requests to access the datasets should be directed to Andrea Cherrington, MD, MPH, acherrington@uabmc.edu.The studies involving human participants were reviewed and approved by University of Alabama at Birmingham, Office of the Institutional Review Board. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.ACA contributed to the design of the study, analyzed the data, wrote the manuscript, and revised prior drafts of the manuscript for intellectually important content. CH contributed to the design of the study, wrote the manuscript, and revised prior drafts of the manuscript for intellectually important content. ACA, CH, and CP assisted LJ with the analysis and revised the manuscript for intellectually important content. EL contributed to the conception and design of the study, provided expertise on the analysis plan, and revised the manuscript for intellectually important content. AAA contributed to the design of the study and provided expertise on survey implementation. LJ takes responsibility for the integrity of the data and the accuracy of the data analysis. CP provided input on the analysis plan and revised prior drafts of the manuscript for intellectually important content. ACA and AC conceived and designed the study, assisted in data analysis and interpretation, wrote parts of the introduction and discussion section, and revised prior drafts of the manuscript for intellectually important content. The survey data from reported here were collected from Alabama Medicaid Agency recipients with diabetes mellitus. All authors contributed to the article and approved the submitted version.The project described was supported by the National Institute of Diabetes and Digestive and Kidney Diseases . Support was also provided by UAB Diabetes Research Center .The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institutes of Health, or the Alabama Medicaid Agency. Representatives for the Alabama Medicaid Agency were provided an opportunity to review and provide comments on the manuscript prior to submission. This manuscript was not prepared in collaboration with the Alabama Medicaid Agency and does not necessarily reflect the opinions or represent the official views of the Alabama Medicaid Agency.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Vaccine hesitancy has been an ongoing complex public issue in the Philippines posing threats to progress against preventable outbreaks and significant morbidity and mortality from COVID-19. Patients with cancer were not included in the initial vaccine trials against COVID-19 hence the plausible explanation behind vaccine hesitancy in this population. This study attempts to determine the factors affecting a patient diagnosed with breast cancer to receive COVID-19 vaccine based on constructs from the Health Beliefs Model (HBM).To determine the factors affecting a Filipino diagnosed with breast cancer to receive COVID-19 vaccine, namely; perceived susceptibility and severity to COVID-19 and perceived benefits and barriers to getting a vaccination against COVID-19.A single- center, descriptive, cross-sectional study in patients diagnosed with breast cancer was conducted to assess COVID-19 vaccine hesitancy.A total of 85 eligible breast cancer patients were included in the analyses. Age, socio-economic factors, and presence of co-morbidities and metastasis were not significantly associated with COVID-19 vaccine hesitancy. Concerns on efficacy, safety, faulty or fake vaccine, as well as if the vaccine was taken by many in the public were significantly associated with hesitancy (p <0.05) when taken as individual factors. The perception of COVID-19 vaccine safety under the perceived barriers construct was found to be the only significant factor to predict vaccine hesitancy .Interventions that focus on perceived barriers are most crucial in order to increase vaccination rate among breast cancer patients.No significant relationships.