Subsequently, we tested the hypotheses across two studies . In alignment with the ceiling effect of human energy theory, the three-way interaction results across the samples consistently indicate that high supervisory political support (SPS) significantly strengthens the negative interactions of psychological health risk factors and high job tension as adverse working conditions (SDG-8) on working-condition-related well-being as the human sustainability dimension (SDG-3). Similarly, synergistic effects were found of the side effects of work on health, high job tension, and high SPS on well-being in sample 3. We discuss theoretical and future research for human sustainability from occupational health and sustainable HRM perspectives.We explored the interaction of the United Nation’s sustainable development goals to facilitate human sustainability using occupational health and sustainable HRM perspectives. In Study 1 ( United Nations has encouraged organisations to voluntarily adopt sustainable development goals (SDGs) in business strategies to promote human sustainability, which many global companies have embraced. In this context, the perspective of interactions of SDGs for human sustainability at work  emphasisThe human dimension of sustainability ,6 uses hThe human energy discussed in the definition of HHW represents a source of “fuel” necessary for an employee’s work performance and to involve in non-work activities to enhance well-being . When thThe ceiling effect of human energy theory extends the Conservation of Resources (COR) theory . The CORIn the health literature, well-being includes health and constitutes a unifying concept  valuable for health improvement . In the Previous studies in the occupational health and management literature explored using COR theory the buffering role of organisational resources  on the relationship between job stress and employee well-being . EvidencUnderstanding the synergistic, adverse effects of work characteristics and SPS on organisation and stakeholder  outcomes from the ceiling effect of human energy viewpoint is essential for the emerging field of sustainable HRM to gain insights into the temporal perspective  on the oThe three-sample study fills gaps in occupational health, sustainable HRM, and stress literature, from the harm of work and COR perspectives, by demonstrating the bundle or synergistic effects of HHW, job tension, and SPS on employee well-being. Specifically, SPS manifests when a leader exercises subordinate-benefitting political influence to acquire and distribute resources and remove roadblocks impeding contributions and well-being . In termThis research makes multiple contributions. First, previous studies in the COR literature have used rest or recovery to manage employee engagement and burnout caused by loss cycles at work . Our stuSecond, the job demand-resources (JD-R) theory of work stress acknowledges the ceiling effect hypothesis of employee engagement for job performance from the individual employee-level perspective . HoweverOver the last two decades, as an emerging discipline within HRM, sustainable HRM has been defined in several ways, see review by Macke and Genari . We chosFirst, the theory of work harm ,22 buildHHW includes three reflective dimensions highlighting work restrictions’ unique effects on employee health ,8. SpeciRFPH expands on the manifestation or leading sign attribution of work harm, emphasising the risks of work restrictions on an employee’s cognitive and behavioural conditions  that facilitate negative health issues. Identifying work restrictions for employees helps identify the risk factors that mitigate early to prevent or delay the onset of work-related diseases . SE emphasise the causal attribution of HHW, which is about the ‘unintended’ adverse side effects imposed on employees while an organisation pursues its ‘intended’ business goals. For example, work intensification organisations use to achieve intended improved business bottom-line goals imposes unintended adverse effects on employees, such as excessive use (4 to 10 large cups a day) of coffee and alcohol. These unintended adverse effects of HHW are likely to lead to work-related health problems .Finally, the synthesis effect of sustainable HRM indicates that improved organisational performance and simultaneously reducing HHW operate as two mutually reinforcing polarities ,26. ThusHRM policies and practices set job quality expectations for employees to perform . These jEmployee well-being is understood in the literature from the context-free  perspectA meta-analysis revealed that experiencing job tension by employees is consequential of the work environment that negatively affects employee well-being . FurtherThe hindrance stressor perspective of the challenge-hindrance stress model  maintainFirst, work recovery experience focuses on restoration after a stressful job situation to improve employee health. However, HHW addresses the restrictions imposed by work on employees to involve in non-work activities to achieve positive health and well-being outcomes. Second, HHW expands the positive health perspective, which advocates a proactive approach to identifying work-related psychological disorders and chronic disease indicators to enhance well-being. Hence, the dimensions of HHW are ‘leading’ indicators for employee positive well-being outcomes, instead of the work recovery experience which typically emphasises mood regulation and job-stress coping as ‘lagging’ indicators of work .Sinelnikov et al.  explaineA meta-analysis on job stress revealed that employees who experienced high job tension are most likely to have reduced levels of well-being . These eThe combined adverse effects of HHW and job tension on well-being are explored based on the self-regulatory depletion mechanism of conservation of resources (COR) theory . The selH1A. Job tension will moderate the negative interaction effects of the risk factors of work on psychological health (RFPH) on well-being. Specifically, the negative relationship between RFPH and well-being will be stronger when job tension is high versus low.H1B. The work restrictions on health (WRH) will moderate the negative interaction effects of job tension on well-being. Specifically, the negative relationship between WRH and well-being will be stronger when job tension is high versus low.H1C. Job tension will moderate the negative interaction effects of the side effects of work for health (SE) on well-being. Specifically, the negative relationship between SE and well-being will be stronger when job tension is high versus low.Contemporary work settings are characterised by ambiguity and uncertainty, self-serving behaviour, and competition for limited resources to manage work demands. In this context, SPS, which is different from supervisory support, focuses on supervisors’ non-sanctioned  actions taken to enhance the well-being of one’s subordinates . HoweverIn the organisational politics literature , politicJob demand-resources theory examines the ceiling effect hypothesis of employee engagement for performance . FurtherH2A. The high SPS strengthens the negative interaction effects of risk factors of work on psychological health (RFPH) and job tension on well-being. Specifically, the proposed negative effect in Hypothesis 1A is stronger when high SPS is present.H2B. The high SPS strengthens the negative interaction effects of work restrictions on health (WRH) and job tension on well-being. Specifically, the proposed negative effect in Hypothesis 1B is stronger when high SPS is present.H2C. The high SPS strengthens the negative interaction effects of the side effects of work on health (SE) and job tension on well-being. Specifically, the proposed negative effect in Hypothesis 1C is stronger when high SPS is present.A three-sample study design tested the hypothesised three-way interaction on well-being to address method concerns and increase confidence in the findings relative to single-study designs .M = 1.54, SD = 0.50), averaged 37 years of age , and reported 40 h of work per week .Consistent with prior investigations , studentM = 1.47, SD = 0.51), approximately 36 years old , and worked 39 h per week .We distributed surveys to all 346 employees of a local municipality via email. The municipality resided in the Southeast United States. After two weeks and one prompt, we received 261 surveys (response rate of 80%). However, we used the screening procedures described above, requiring the elimination of 14 surveys. Participants worked in representative job titles . The sample was 47% males , and 49 percent aged between 26 years and 50 years . Thirty percent of participants completed an undergraduate degree , and 56 percent worked more than 40 h per week .We distributed an information letter to a sample of 320 employees from six companies in Australia, which included an URL to access a web-based questionnaire. A total of 255 usable questionnaires were collected (response rate of 80%). 52% of participants were females  and 7 (strongly agree) as endpoints.We measured job tension with House and Rizzo’s  five-iteIn the occupational health and management literature, there are different measures for employee well-being covering work- and non-work-related characteristics ,47. In tThe existing scale includes three dimensions: work restrictions on health (WRH), the risk factors of work on psychological health (RFPH), and the side effects of work for health (SE) . The dimWe measured SPS using Kane-Frieder et al.’s  five-iteA meta-analysis found that employee characteristics, such as increased age, reduced job tension, and increased well-being outcomes . FurtherWe used hierarchical moderated multiple regression analyses to explore the three-way interactions of dimensions of HHW and job tension on well-being (SPSS 27). We performed collinearity diagnostics to evaluate the impact of method variance on study findings. Specifically, we considered variance inflation factors (VIF), which measure the magnitude of collinearity among predictors of a regression model . FurtherWe present descriptive statistics  for Samples 1–3 in We conducted a series of CFAs to demonstrate the independence of study variables in Sample 1. We used six fit indices , includiThese include employee well-being (EW); risk factors of work on psychological health (RFPH); work restriction on health (WRH); side effects of work for health (SE); job tension (JT); supervisor political support (SPS).p < 0.05) and Sample 3 . Furthermore, there exists a significant negative relationship between WRH and well-being in Sample 3  but not in Sample 2 . Lastly, there is no significant relationship between SE and well-being in Samples 2 and 3  and 3 . However, this interaction was significant for WRH , SE , and job tension on well-being, respectively, only among Sample 3. Hence, we rejected Hypothesis 1A. Conversely, Hypothesis 1B and Hypothesis 1C were partially supported.We report the effects of the interactions of each HHW dimension  and job tension on well-being for Samples 2 and 3 see . In thesSE = 0.01, p < 0.05) and 3 . Further, we report a significant three-way interaction of SE, job tension, and SPS on well-being . We found no three-way interaction (see p ns) and 3 . Hence, Hypotheses 2A and 2C were accepted, while Hypothesis 2B was rejected. Lastly, regressions revealed that variance inflation factors were below 2.0, highlighting that multicollinearity was not overly problematic in the study.We report the three-way interaction effects of each HHW dimension with job tension and SPS on well-being in eing see  only in tion see  of WRH, We used a method suggested by Dawson and Richter  to deterThe slope of the relationship between RFPH and well-being is negative and significant in Samples 2, and 3 for the “High job tension—High supervisor political support” condition  Line (1) in The slope of the relationship between SE and well-being is negative and significant only in the “High job tension—High SPS” condition for Sample 3 (difference of −0.26). Line (1) in We conducted a three-sample study to investigate the three-way interaction or synergistic effect of HHW , job tension, and SPS as an organisational resource on well-being as a work-related well-being dimension of human sustainability. Our study builds upon the earlier conceptualisation of all study variables to establish that these content domains are separate and distinct by using sample 1. A previous study from the sustainable HRM literature  found thThe study findings extend empirical evidence of the complementary or cumulative effect of HHW and job tension on well-being as work characteristics for well-being. Previous studies  exploredThere is no evidence of the envisaged negative complementarity effects between RFPH and job tension on well-being among both samples. Research methods on moderation study indicate that when there is a weak link between the independent variable and the outcome variable in the presence of a moderator, it is helpful to explore with an alternative/additional moderator or mediated moderation . Hence, This study is the first in the occupational health, sustainable HRM, and work stress literature exploring the complementarity of dimensions of HHW and job tension on well-being hypotheses. Our study provides empirical evidence to extend the attribution theory of harm of work, COR theory, and the ceiling effect of human energy theory from sustainable HRM for understanding the complementary adverse effects of HHW and job tension on well-being to plan organisational-level interventions for SDG-8 and SDG-3 to enhance human sustainability.First, based on the attribution theory in the JD-R model, the strength of association between the attribution of the independent variable  and outcome variables  was explained as a function of moderators . SimilarThe study findings provide empirical evidence to the stimulus-source attribution perspective of harm of work theory in explaining that the function of WRH is negatively related to well-being when high job tension exists at work. When work restricts employees from being socially and physically reinvigorating activities for positive health, as a stimulus source for harm of work, it complements the negative effect of high job tension on employee well-being. Drawing from the causal attribution aspect of harm of work theory, the findings contribute to occupational health and sustainable HRM literature that the negative relationship between SE and well-being was buffered by high job tension at work. For example, work’s unintended adverse consequences or side effects on employee health, imposed by work practices while attempting to achieve organisational goals, negatively buffer well-being when high job tension is present.Second, our study provides ample empirical evidence for understanding the complementary negative effects of each of the two dimensions of HHW  and high job tension on well-being. Furthermore, outlining the self-regulatory depletion mechanism of COR theory , we explThird, studies in JD-R and JD-C from the occupational health literature explore the three-way interaction effect of internal resources, job control, and job stressors on employee well-being and well-being . HoweverIn expanding empirical evidence on previous three-way interaction and two-way interaction studies in the occupational health, job strain, and sustainable HRM literature, the current study suggests that high SPS does not represent the resource gain cycle of COR theory to buffer the negative complementarity between the two dimensions of HHW (RFPH and SE) and job tension on well-being. Hence, the findings extend the COR theory with empirical evidence for the ceiling effect of human energy theory from the occupational health and sustainable HRM perspectives .Fourth, the ceiling effect findings extend the temporal aspect  of the cAlthough this study has many strengths, including replicating and extending findings on the synergistic effect of study variables on well-being across three unique samples, it is not without limitations. We used convenience sampling to identify full-time employees for the three different samples in the study. Future studies should benefit from attempting to identify a representative sample of the larger group of full-time employee characteristics based on gender, age groups, and industry types. Despite controlling for similar constructs , and testing multiple models by conducting CFA to demonstrate the independence of study variables to explore well-being, furthering this effort will facilitate better conceptualising and developing theoretical space for organisations to understand subjective employee well-being to improve human sustainability.A single cross-sectional, self-report data collection introduces common method bias (CMS) into the results. We used several procedural remedies indicated by Podsakoff et al.  to mitigFuture research would benefit from a longitudinal design to explore the dynamics of complementary and synergistic effects of HHW along with other employment practices  from the temporal perspective to understand the ceiling effect of human energy at work on job performance, employee engagement and human sustainability outcomes . This study’s results failed to support the envisaged synergistic effect of WRH on well-being. Hence, future research can also explore the indirect effect of prosocial job design on the cumulative conditional level of negative interactional effects of HHW and job tension using a mediated moderation study design .Our findings promote sustainable HRM practices as an institutional or organisational response to the UN’s SDG-8 and SDG-3. Work intensification has become a dominant source that facilitates harm to work and job tension in increased absenteeism, presenteeism, and employee turnover and creates a competitive disadvantage to organisations and social costs to stakeholders ,25. HencIn the occupational health and sustainable HRM literature, organisations cannot avoid imposing social costs of harm of work on employees while the organisation focuses on improved performance . However, organisations also have a corporate social responsibility to minimise such harm of work imposed by adverse working conditions (SDG-8) on employee well-being (SDG-3). Practitioners know from the JD-R literature that adequate organisation resources will support employees to buffer well-being when employees experience high job tension . HoweverFinally, a literature review article revealed for practitioners that improvements in well-being and job performance are associated with a bundle of employment practices that includes job design which focuses on employee welfare . Hence, This three-sample study facilitates our understanding of the adverse synergistic effects of HHW, job tension, and SPS on employee well-being as a dimension of human sustainability. Our findings provided evidence for the ceiling effect of human energy when SPS as an organisational resource was inadequate to buffer the adverse complementarity effect of the dimensions of HHW (RFPH and SE) and high job tension as working conditions (SDG-8) on employee well-being as a human sustainability dimension (SDG-3). This study meaningfully extends the occupational health, sustainable HRM, and COR literature that human energy at work is not infinite when employees encounter cumulative adverse working conditions. Hence, it is crucial to examine the bundle of negative effects instead of attempting to manage a single negative effect of work in understanding the sustainability of human energy to enhance employee well-being as a dimension of human sustainability and subsequently benefit organisations.


Keratoconus (KC) is a serious disease that can affect people of any race or nationality, although the exact etiology and pathogenic mechanism are still unknown. In this study, thirty-two FDA-approved ophthalmic drugs were exposed to virtual screening using docking studies against both the MMP-2 and MMP-9 proteins to find the most promising inhibitors as a proposed computational mechanism to treat keratoconus. Matrix metalloproteinases (MMPs) are zinc-dependent proteases, and MMP inhibitors (MMPIs) are usually designed to interact with zinc ion in the catalytic (CAT) domain, thus interfering with enzymatic activity. In our research work, the FDA-approved ophthalmic medications will be investigated as MMPIs, to explore if they can be repurposed for KC treatment. The obtained findings of the docking study suggest that atenolol and ampicillin are able to accommodate into the active sites of MMP-2 and MMP-9. Additionally, both exhibited binding modes similar to inhibitors used as references, with an ability to bind to the zinc of the CAT. Molecular dynamic simulations and the MM-GBSA binding free-energy calculations revealed their stable binding over the course of 50 ns. An additional pharmacophoric study was carried out on MMP-9 (PDB ID: 1GKC) using the co-crystallized ligand as a reference for the future design and screening of the MMP-9 inhibitors. These promising results open the door to further biological research to confirm such theoretical results. Keratoconus (KC) is the most common primary cause of corneal ectasia. It commonly strikes in one’s second decade of life, affecting people of all races and nationalities. In the general population, the prevalence is estimated to be 54 per 100,000 . Hay fevThe disease’s stage and progression determine the treatment of keratoconus. Spectacles can give an acceptable vision to people in the early stages of their condition, and they are beneficial for those with a visual acuity of 20/40 or greater. On the other hand, spectacles cannot rectify irregular astigmatism, and in such circumstances, hard contact lenses can improve the patient’s vision . PenetraMany investigations have found higher levels of collagenolytic and gelatinolytic activities in laboratory cultures of KC. Collagenases and gelatinases are members of the matrix metalloproteinases (MMPs) family of zinc-dependent proteins . CompareI and marimastat II [III and the mercapto group of rebimastat IV  program was used in the current docking study. The validation of the docking accurately reproduced the binding conformation of the co-crystallized ligands with MMP proteins. The RMSD values were calculated between the co-crystallized poses and the docked poses of the same ligands in MMP-2 (PDB ID: 1HOV) and MMP-9 (PDB ID: 1GKC). Minor deviations of 1.30 and 0.75 Aectively . Such re−1, as shown in I52) and our top hits was then performed for a comparative study of how well our compounds conform to the intended design.All the selected compounds showed favorable binding, demonstrating ∆G (binding free energies) values in negative Kcal.molI52  occupied the MMP-2 active site via the formation of six hydrogen bonds and eight hydrophobic interactions. The fluoroquinolone nucleus formed three hydrogen bonds with Leu83 and Ala84, as well as six hydrophobic interactions with zinc, Leu83, and His120. The piperazine arm was incorporated in three hydrogen bonds with Leu137, Ala139, and Thr143, as presented in −1) scores, as shown in The tested compounds revealed to be able to bind into MMP-9 and showed negative ∆G  to the active site of MMP-9, it showed six hydrogen bonds with Gly186, Leu188, Ala189, Tyr393, and Tyr423, in addition to two hydrophobic interactions with Leu188. The hydroxamate group interacted as expected with the zinc of the CAT, as presented in By examining the binding interactions of the co-crystalized ligand  and nine hydrophobic interactions  .Finally, the binding of ganciclovir was through four hydrogen bonds with Leu188, Glu402, and Pro421. Four hydrophobic interactions were also detected . It was also able to bind with zinc ion through a metal–acceptor interaction .Because atenolol and ampicillin were the most promising compounds that achieved high docking scores and similar binding modes to co-crystallized ligands with the ability to interact with zinc ions in both enzymes, they were both promoted for further analysis through molecular dynamics.0 deviation for MMP-2 and MMP-9, respectively. Furthermore, both atenolol and ampicillin exhibited stable conformations with an RMSD  of the residues of the proteins and ligand atoms across the simulation time. Consistent with the calculated RMSD, the protein residues showed a low degree of fluctuations, especially with the ones in contact with the ligands as shown in 1A0 only . These uFor a better understanding of the binding modes, a further analysis of the interactions throughout the whole 50 ns simulation time was performed . For MMPOne of the most commonly used methods for calculating the binding free energy is molecular mechanics–generalized born surface area (MM-GBSA). The lower a ligand-protein complex’s projected binding free energy is, the more stable the complex is expected to be, and the higher the ligand’s activity and potency . Both coThe prospect of repositioning ampicillin for KC treatment may seem beneficial especially for complicated cases suffering from secondary bacterial infections. However, its unattended use for prolonged periods of time increases the risk of bacterial resistance. For this purpose, we extended our study on the MMP-9 inhibitors to propose pharmacophoric features with a high potential of a MMP-9 inhibitory goal for future use.NFH  during its interaction with the receptor. The library was then screened, and fit value data were calculated  was used to generate the pharmacophore model using the Discovery studio software. In this test, the protocol of receptor-ligand pharmacophore generation was applied. In this protocol, the software identifies the essential features of lculated . Ampicil0 radius (NFH.The formed pharmacophore model consisted of six features: two H-bond donors (HBD), two H-bond acceptors (HBA), and two hydrophobic centers (H). The features were distributed in a pyramidal shape with each feature occupying a 1.6 A0 radius . In acco0 radius  demonstrI52 and NHF  and interacted with the zinc ion of the CAT successfully. Subsequent molecular dynamic simulations and MM-GBSA calculations point to the stability of the binding of both drugs to the respective enzyme, thus adding to the potential of both compounds in KC management. The dual potential properties of ampicillin for the treatment of KC, especially with bacterial infections, pushed for the design of alternatives that could be used for prolonged treatment times without risk of bacterial resistance. An additional pharmacophore study was carried out using the co-crystallized ligand of MMP-9 (PDB ID: 1GKC) as a reference molecule for future designs. These encouraging findings pave the way for additional clinical investigations to confirm such theoretical findings.In an attempt to fasten the drug discovery process, a repositioning approach was enforced to discover potential medications for KC in a cost/efficient manner. Because high levels of collagenolytic and gelatinolytic actions were observed, collagenase and gelatinases became a promising target for tackling KC. Among those proteolytic enzymes are MMP-2 and MMP-9. Both are metalloenzymes that are characterized by the presence of zinc ion in the CAT. Thus, inhibition techniques focused on drugs that can interact with zinc ions through their ZBGs. As a result, thirty-two FDA-approved drugs were subjected to virtual screening through docking against MMP-2 and MMP-9 proteins to identify the most promising inhibitors as a proposed computational mechanism to treat KC. The docking results showed the ability of atenolol and ampicillin to accommodate well into the active sites of MMP-2 and MMP-9, respectively. Additionally, both exhibited similar binding modes as https://pubchem.ncbi.nlm.nih.gov/) (accessed on 1 April 2022) and sketched using ChemBioDraw Ultra 14.0 and saved in MDL-SD file format.The designed compounds’ structures were retrieved online  (accessed on 1 April 2022). Molecular operating environment was used for docking. At first, the protein files were prepped using built-in “Quickprep” function. Initial validation was performed through docking of each co-crystallized ligand to its protein file, followed by the calculation of root mean square deviation (RMSD) between the docked pose and the co-crystallized one. After successful validation, the library of compounds was imported and prepped into MOE database file, that was then docked using “Induced fit” protocol. The interactions were then viewed using Discovery Studio Visualizer 2021 [The crystal structures of MMP-2 and MMP-9  as a reference molecule. The tested compounds were used as a training set. In this protocol, we used the following features in pharmacophore generation: (i) hydrogen bond donor (HBD), (ii) hydrogen bond acceptor (HBA), (iii) hydrophobic aliphatic (HA), (iv) hydrophobic aromatic (HAr), and ring aromatic (RA). Then, the ligand pharmacophore mapping protocol was used in the virtual screening process. The most predictive model was used as 3D queries to identify compounds with high fit values ,37,38,39


A 58-year-old female patient presented at cardiology outpatient clinic with palpitation. The 12-lead electrocardiography on admission revealed monomorphic bigeminy premature ventricular contractions (PVCs) showed a left bundle-branch block configuration, monophasic R wave in lead I and aVL and precordial transition in V3 lead. Cardiac electrophysiological study was performed to patient. Activation mapping guided by three-dimensional electroanatomic system was done. The earliest ventricular activation was observed in the para-hisian region with the largest His potential (0.6 mV) during PVC. Due to the risk of atrioventricular (AV) block, radiofrequency (RF) ablation was planned to the region, where the His potential amplitude was lower (0.2 mV), the AV ratio was <1, and ventricular activation preceded the QRS onset by 37 ms. Subsequently, irrigated RF current was delivered in the distal His region with power starting at 15 W after PVC was suppressed, RF delivery was applied for a total of 90 s with gradually increasing power to 25 W. After ablation, under isoproterenol infusion, burst pacing from the right ventricle no PVCs/VTs was observed. A gradual RF energy application, a detailed activation mapping, and the distance from the largest His potential increase the likelihood of success in para-hisian PVC ablation. Most idiopathic premature ventricular contractions (PVCs) originate from the right or left ventricular outflow tracts and aortic sinuses of Valsalva; however, it may also arise from the para-hisian region, even though it is rare . The radHere, we reported a case of successful catheter ablation of PVCs arising from the para-hisian region with a three-dimensional (3D) electroanatomic mapping system, and ablation techniques for such cases.A 58-year-old female patient presented at the cardiology outpatient clinic with palpitation and dyspnea. The patient’s 12-lead electrocardiography (ECG) on admission showed monomorphic bigeminy PVCs. In addition, PVC showed a left bundle-branch block configuration, monophasic R wave in lead I and aVL, and precordial transition in V3 lead . His symAfter informed consent was obtained from the patient, a cardiac electrophysiological study was performed under a fasting non-sedated state and antiarrhythmic agents had been discontinued for at least five half-lives before the study. For mapping and pacing, a quadripolar catheter was positioned via right femoral vein at the right ventricular (RV) apex and a deflectable decapolar catheter in the coronary sinus. Mapping and pacing were performed using a 3.5 mm open-irrigated-tip catheter . Activation mapping guided by three-dimensional electroanatomic system was performed to identify the earliest site of ventricular activation the PVCs. The activation time was measured from the onset of the bipolar electrogram from the distal bipole of the mapping catheter to the earliest onset of the QRS complex in any of the 12 ECG leads. During the PVC, the earliest ventricular activation was identified at the His-bundle region, where a high amplitude His-bundle electrogram could be recorded during the sinus rhythm. PVC activation preceded QRS onset by 41 ms was recorded on the bipolar recording with QS pattern on the unipolar recording and there was a 0.6 mV His potential .It was decided not to perform ablation at the region with the largest His potential due to the AV block risk. RF ablation was planned to the region, where the His potential amplitude was lower (0.2 mV), the AV ratio was <1, and ventricular activation preceded the QRS onset by 37 ms . SubsequHere, we reported a case of successful catheter ablation of PVCs arising from the para-hisian region with a 3D electroanatomic mapping system. The study by Yamauchi et al.  demonstrWe performed RF catheter ablation of PVCs originating from the para-hisian region using a 3D electroanatomic mapping system. The gradual RF energy delivery and the detailed activation mapping along with the distance from the largest His-bundle potential decreased the AV block risk. We believe that RF catheter ablation treatment, which will be applied to the high-burden PVC origin with a limited response to pharmacotherapy, can be also preferred in the para-hisian regions.


Since 2010, the Ovation Abdominal Stent Graft System has offered an innovative sealing option for abdominal aortic aneurysm (AAA) by including a sealing ring filled with polymer 13 mm from the renal arteries. In August 2020, the redesigned Ovation Alto, with a sealing ring 6 mm closer to the top of the fabric, received CE Mark approval.This registry study aims to evaluate intraoperative, perioperative, and postoperative results in patients treated by the Alto stent graft (Endologix Inc.) for elective AAA repair in a multicentric consecutive experience.All consecutive eligible patients submitted to endovascular aneurysm repair (EVAR) by Alto Endovascular AAA implantation will be included in this analysis. Patients will be submitted to EVAR procedures based on their own preferences, anatomical features, and operators experience. An estimated number of 300 patients submitted to EVAR with Alto stent graft should be enrolled. It is estimated that the inclusion period will be 24 months. The follow-up period is set to be 5 years. Full data sets and cross-sectional images of contrast-enhanced computed tomography scan performed before EVAR, at the first postoperative month, at 24 or 36 months, and at 5-year follow-up interval will be reported in the central database for a centralized core laboratory review of morphological changes. The primary endpoint of the study is to evaluate the technical and clinical success of EVAR with the Alto stent graft in short- (90-day), mid- (1-year), and long-term (5-year) follow-up periods. The following secondary endpoints will be also addressed: operative time; intraoperative radiation exposure; contrast medium usage; AAA sac shrinkage at 12-month and 5-year follow-up; any potential role of patients’ baseline characteristics, valuated on preoperative computed tomography angiographic study, and of device configuration (number of component) in the primary endpoint.The study is currently in the recruitment phase and the final patient is expected to be treated by the end of 2023 and then followed up for 5 years. A total of 300 patients will be recruited. Analyses will focus on primary and secondary endpoints. Updated results will be shared at 1- and 3-5-year follow-ups.The results from this registry study could validate the safety and effectiveness of the new design of the Ovation Alto Stent Graft. The technical modifications to the endograft could allow for accommodation of a more comprehensive range of anatomies on-label.ClinicalTrials.gov NCT05234892; https://clinicaltrials.gov/ct2/show/NCT05234892PRR1-10.2196/36995 An abdominal aortic aneurysm (AAA) is a dilatation in the lower part of the major vessel (aorta) that supplies blood to the body. The most accepted definition of AAA is based on a diameter of 3.0 cm or more, which is usually higher than 2 SDs above the mean diameter for men ,2. Over Thirty years ago, Juan Parodi  developeThe device under investigation represents the evolution of the low-profile Ovation Prime and iX endograft  17]. Th. Th17]. Iliac limbs have also not changed and are deployed through a 12-15-Fr delivery system (outer diameter) with various lengths and diameters ranging from 80 to 160 mm and 10 to 28 mm, respectively. The new feature of Ovation Alto is the relocation of the proximal sealing ring at 7 mm from the main body fabric’s proximal edge. In the previous versions, this distance was 13 mm. The low-permeability graft material and the suprarenal 35-mm free-flow stent remained unchanged. It is still delivered via a flexible, hydrophilic-coated, low-profile delivery system .Another design improvement is the integration of a compliant balloon within the delivery system. The balloon is highlighted by a proximal radiopaque marker that coincides with the first sealing ring location, helping in the precise placement of the endograft.The deployment of the device is performed in a 2-time maneuver . InitialOther minor modifications of the Ovation Alto design are as follows: (1) the inner diameter of the docking limb has been increased to 11 mm for all main body sizing; (2) a more definite web enriched the device bifurcation to avoid a prolapse of the contralateral limb during guide-wire access; (3) the aortic body limbs were offset by 5 mm to improve their identification during the procedure.According to the current instruction for use, the following anatomical criteria are required :adequate iliac/femoral access compatible with vascular access techniques , devices, or accessories;a proximal aortic landing zone for the sealing ring 7 mm below the inferior renal artery;an aortic sealing zone consisting of healthy aorta defined asa lack of significant thrombus greater than 8 mm in thickness at any point along the aortic circumference at the level of 7 mm below the inferior renal artery;a lack of significant calcification at the level of 7 mm below the inferior renal artery;conicity <10% as measured from the inferior renal artery to the aorta 7 mm below the inferior renal artery;an inner wall diameter of no less than 16 mm and no greater than 30 mm at 7 mm below the inferior renal artery; andan aortic angle of ≤60°.a distal iliac landing zone:with a length of at least 10 mm andwith an inner wall diameter no less than 8 mm and no greater than 25 mm.The contraindications for Alto stent-graft implantation according to the instruction for use are:patients who have a condition that threatens to infect the graft andpatients with known sensitivities or allergies to the device materials .All consecutive eligible patients submitted to EVAR by Alto Endovascular AAA implantation will be included in analysis. Patients will be submitted to EVAR procedures based on their own preferences, anatomical features, and operators experience.An estimated number of 300 patients submitted to EVAR with Alto stent graft will be enrolled. It is estimated that the inclusion period will be 24 months. The follow-up period is set to be 5 years. Prior to enrollment into the clinical investigation, patients will be evaluated by their physician for inclusion criteria. Each patient’s medical condition should be stable, with no underlying medical condition that would prevent them from performing the required testing or from completing the study. Patients should be geographically stable, willing and able to cooperate in this clinical study, and remain available for midterm follow-up. Patients who do not wish to participate in this study can obtain the best available EVAR therapy as indicated; refusal to participate in this study will in no way affect their care at the institution. Inclusion and exclusion criteria are detailed in This study respects all the principles reported in the current version of Helsinki declaration (2013). AAA morphology will be assessed by OsiriX MD  on a computer (with Mac operating system) in a preoperative, contrast-enhanced, computed tomography angiographic (CTA) study. CTA must be performed with a biphasic acquisition protocol (unenhanced and contrast-enhanced scanning with a bolus tracking system) and reconstructions to 1-mm slices. All measurements  will be evaluated on a workstation with dedicated reconstruction software and center lumen line analysis and multiplanar reconstruction.Inclusion CriteriaPatients with abdominal aortic aneurysm who are scheduled for elective repair according to Endologix Alto endograft device’s instruction for use.Patient is willing to comply with specified follow-up evaluations at the specified times for the duration of the study.Patient is aged over 18 years.Patient, or his/her legal representative, understands the nature of the procedure and provides written informed consent prior to enrollment in the study.Exclusion CriteriaAbdominal endovascular aneurysm repair performed in an urgent/emergent setting.Patients treated outside Endologix Alto endograft device’s instruction for use.Patients refusing treatment.Patients for whom antiplatelet therapy, anticoagulants, or antihypertensive drug are contraindicated.Patients with a history of prior life-threatening contrast medium reaction.Life expectancy less than the follow-up period.A patient is considered enrolled in the study if he/she has full compliance with the study inclusion and exclusion criteria and after successful EVAR procedure at completion angiography.Clinical data will be collected at patients’ enrollment, EVAR procedure, discharge, planned follow-ups , unplanned or interim follow-ups, and patient death. CTA within 90 days, 24 or 36 months, and 5 years after the index procedure is mandatory. Duplex ultrasound scan will be performed at the same follow-up interval, and also at 12, 24, 36, and 48 months. A new CTA will be performed in case of unexpected events during follow-up. The follow-up protocol is based on the most recent European guidelines for the management of the AAAs [The primary endpoint of the study is to evaluate the technical and clinical success of EVAR with Alto stent graft in short- (90-day), mid- (1-year), and long-term (5-year) follow-up periods. Technical success is defined as the correct graft deployment without any unintentional occlusion of the aortic visceral branches or both hypogastric arteries, with aneurysm exclusion confirmed by the intraoperative angiography, without signs of type I/III endoleak or conversion to open surgery or mortality. Clinical success includes successful deployment of the endovascular device at the intended location without death as a result of aneurysm-related treatment, type I or III endoleak, or graft infection or thrombosis, aneurysm expansion (>5 mm), aneurysm rupture, or conversion to open repair. Moreover, the presence of graft dilatation of 20% or more by diameter, graft migration, or a failure of device integrity will be evaluated.The clinical and technical successes are defined “assisted” in case of unplanned endovascular procedures, or “secondary” if unplanned surgery is necessary .The following secondary endpoints will be also addressed: (1) operative time; (2) intraoperative radiation exposure; (3) contrast medium usage; (4) AAA sac shrinkage at 12-month and 5-year follow-up; (5) any potential role of patients’ baseline characteristics, valuated on preoperative CTA, and of device configuration (number of component) in primary endpoint.P values <.05 will be defined as significant.Patient data will be captured electronically using a computer-based platform accessible to all investigators. Descriptive data summaries will be used to present and summarize the collected data. For categorical variables , frequency distributions and cross tabulations will be given. For numeric variables , range, mean, median, and SD will be calculated. For all variables, a 95% CI for the relevant parameters of the underlying distribution will be calculated. For all time-dependent events, life tables will be calculated using the Kaplan-Meier estimate method for a period starting on the date of the procedure up to and including all follow-up visits. Stratification to risk factors will be performed and the log-rank test will be used to compare between the different outcomes; associated All preoperative and follow-up CTAs were assessed and independently evaluated by 2 experienced vascular surgeons at core laboratory center. Disagreements will be discussed and resolved by consensus.All information and data concerning patients or their participation in this clinical investigation will be considered confidential. Only authorized personnel will have access to these confidential files. Authorized personnel of health authorities will have the right to inspect and copy all records pertinent to this clinical investigation. All data used in the analysis and reporting of this clinical investigation will be anonymized.This study adheres to the guidelines of European Good Clinical Practice (ICH: 6 R2) and adopted by the Italian Agenzia Italiana del Farmaco (AIFA), in accordance to Legislative Decree 196/2003 and 21/2007 of the Italian Ministry of Health. The local institutional review boards of the participating centers were informed of the descriptive, nonexperimental nature of this registry study. The device under investigation is already available for standard clinical practice.The data sets generated during or analyzed during this study will be available from the corresponding author on reasonable request.Patient enrollment started in January 2022. It is anticipated that 300 patients will be recruited to the study. All variables will be evaluated in a dedicated central database. All morphological changes will be examined in a centralized core laboratory. After data analysis, results will be shared with each investigator. Updates to results will be published at 1-year follow-up and at 3-5-year follow-up.The purpose of this registry study is to demonstrate that the adaptive sealing technology of the Alto stent graft is safe and effective in the treatment of infrarenal AAA in different anatomical scenarios.Since its appearance in the market in 2010, the Ovation endograft has offered an innovative sealing concept involving a nonexpansive circumferential apposition of inflatable rings filled by a low-viscosity polymer .The Ovation Alto abdominal stent-graft system received Food and Drug Administration (FDA) approval on March 16, 2020. The commercial launch of the device in the United States was announced on July 30, 2020. On August 5, 2020, Endologix proclaimed CE Mark approval in the European Union for EVAR. In Italy, the commercial launch started in November 2020, in centers having a vast experience with Ovation Prime and iX. The new Alto sealing zone is closer to the renal arteries and may offer sealing in aneurysms with irregular or less than 1-cm long neck. We have already described the possibility to treat juxtarenal aortic aneurysms unfit for open surgery and for fenestrated/branched EVAR. The solution was to perform a physician-modified implantation of Ovation iX, in a procedure termed the “vent” technique. It involves an off-label, aggressive deployment of the sealing ring between 1 and 3 mm below the lowermost renal artery rather than 13 mm. The proximal edge of the collar zone’s fabric was moved down by bare-metal stents contemporarily deployed to assure renal arteries’ patency . The venAn inaccurate deployment of the sealing ring with the previous Ovation version has been described as the cause for an early technical failure . The comThe low-profile delivery system (15 F) establishes small iliac access (>6 mm) with the possibility to perform percutaneous procedures, achieving a reduction in blood loss, groin complications, and earlier discharge.Holden and Lyden  reportedRecently, another initial experience  confirmeGood 5-year EVAR results with the Ovation platform have been reported, demonstrating excellent long-term durability of this endograft, despite 41% of patients having an anatomy unfit for other stent grafts . Results


Reconstruction of massive tibial defects in ankle joint-preserving surgery remains challenging though biological and prosthetic methods have been attempted. We surgically treated a patient with only 18-mm distal tibia remaining and reconstructed with a unique three-dimensional printed prosthesis.A 36-year-old male presented to our clinic with complaints of gradually swelling left calf and palpable painless mass for five months. Imageological exam indicated a lesion spanning the entire length of the tibia and surrounding the vascular plexus. Diagnosis of chondrosarcoma was confirmed by biopsy. Amputation was initially recommended but rejected, thus a novel one-step limb-salvage procedure was performed. After en-bloc tumor resection and blood supply rebuilding, a customized, three-dimensional printed prosthesis with porous interface was fixed that connected the tumor knee prosthesis and distal ultra-small bone segment. During a 16-month follow-up, no soft tissue or prosthesis-related complications occurred. The patient was alive with no sign of recurrence or metastasis. Walking ability and full tibiotalar range of motion were preserved.Custom-made, three-dimensional printed prosthesis manifested excellent mechanical stability during the follow-up in this joint-preserving surgery. Further investigation of the durability and rate of long-term complications is needed to introduce to routine clinical practice. The tibia is the second most frequently affected bone in terms of primary bone sarcomas and it may also be involved in metastatic diseases . While mCases of total tibial reconstruction are rare and only four have been reported where ankle joints were sacrificed with either hindfoot fusion nail or metal tibiotalar components. Compared with a large segment allograft, endoprosthesis was thought to be a more appealing choice –11. The We present here a customized, 3D-printed prosthesis with porous contact surface and extracortical plates for the reconstruction of a massive defect of almost the whole length of the tibia with the preservation of the ankle joint. There is no similar limb salvage and joint-sparing approach reported before.A 36-year-old male was referred to our clinic with complaints of gradually swelling left calf and palpable painless mass since five months ago. Plain radiography revealed irregular punctate calcification within the soft mass silhouette. Magnetic resonance imagery (MRI) images indicated that the lesion formed a large spindle soft tissue mass with a size of 194.3 × 81.8 × 60.8 mm. Sagittal images demonstrated the breach of the tibial plateau and the range of abnormalities was about 300 mm with 28 mm distal tibia intact . The patAccording to the computer-aided, 3D angiography of the lower extremity, the anterior tibial artery, posterior tibial artery, peroneal artery, and vena comitans were wrapped by tumors. Thus, mid-thigh amputation was initially recommended. But the patient firmly refused for psychological and social reasons.Due to the resistance of chondrosarcoma to chemotherapy, a one-step surgery was planned that included joint-preserving tumor resection, contralateral great saphenous vein grafts aided reperfusion of the distal extremity, and prosthetic reconstruction of the bone defect. Considering the massive osseous defect that would be present, the application of customized, 3D-printed implant and patient-specific guide (PSG) was opted.CT scan data in DICOM format was imported into Mimics software  to reversely construct the 3D model. A uniplanar bone resection was employed. Osteotomy plane was defined based on MRI images and measured by the distance from the adjacent joint line with an extra 10-mm tumor-free margin. PSG was designed to be fully fit with the ventral tibia and then fabricated from nylon powder using selective laser sintering technique. After anatomic placement, the PSG could be secured by K-wires via drill sleeves. A cutting platform that provided the osteotomy trajectory and confined the oscillating saw was incorporated . Size ofThe design stemmed from the concept of an essentially extensive proximal tibial replacement incorporating an oncologic knee prosthesis. Mini-extracortical plates were located dorsally and ventrally at the distal margin to prevent sagittal angulation during the early stage of bone growth. One larger extracortical plate extending medially corresponded neatly to the dimensions and shape of the medial malleolus that acted as the main anchorage tool of the implant to the remaining bone segment. Due to the limited residual bone stock and sectional area of the distal tibia, four spikes were used to increase bone contact and prevent excessive medullary violation. The tip of each spike was solid for press-fitting onto the cancellous bone in a cementless manner, while the base was trabecular, fusing with the surrounding porous structures. Screw holes were customized on the middle and lower third of the prosthesis to be fitted with an off-the-shelf L-shape tibial plate .An extensive anteromedial approach was applied. Resection margin of soft tissue was determined according to the MRI images. The PSG, fitting anatomically on the distal tibia, was firmly stabilized with K-wires to facilitate planned osteotomy . Then thThe affected limb was fixed with an extension splint for 4 weeks after the operation. Antithrombotic prophylaxis was performed using low molecular heparin calcium with a dose of 4,000 IU per day. A third-generation cephalosporin was given for 14 days, followed by an oral combination of levofloxacin and rifampicin for one month. Progressive axial weight-bearing exercise was carried out 2 weeks after the operation with a brace. Postoperative X-rays were compared with blueprints to confirm the precision of manufacture and angle stability of the prosthesis .Chest CT was taken every 3 months and contrast-enhanced CT of the lower limbs was taken one year after. The patient underwent evaluations including physical examinations and plain radiography before discharge and 1, 3, 6, 12, and 16 months thereafter.The patient reported no palpable mass or discomfort except for mild edema following long-term standing and was alive without evidence of local recurrence or distant metastasis. No disruption of prosthetic components or aseptic loosening occurred. And no evidence of ischemic necrosis or collapse of the ultra-small bone fragment was observed.Functional evaluation determined at the 16-month mark by Musculoskeletal Tumor Society (MSTS) score  was 5, 4There were some limitations in this report. First, the relatively short follow-up period confined our results. Observation of the durability and long-term complications is needed. Although the functional and oncological outcome was satisfactory, we recognize that this case provided an alternative to amputation and mid-thigh amputation still remains the most reliable strategy for achieving intermediate results. Second, the nature of titanium alloy made it difficult to monitor the degree of osseointegration for making CT and MRI images around the implant distorted unless an amputation specimen is retrieved , 18. EveTreatment of juxta-articular bone tumor remains a challenge. Joint-preserving surgery may provide a similar risk of complications when compared with reconstructions sacrificing joint , with thFor lesions invading the metaepiphysis and the distance between the tumor edge and articular cartilage is less than 1 cm, joint-salvage surgery seemed to be contradicted. A novel adjuvant technique consisting of argon-based cryoablation and transepiphyseal osteotomy was proposed under the circumstances . The shoIn the cases of lesions in the distal tibia, the outcome of ankle endoprosthesis was not ideal due to talar collapse, infection, aseptic loosening, and a diminished maximum angle of plantar flexion , 23, 31.It is challenging to perform joint-preserving surgery using a prosthesis for massive bone defects of total tibial length combined with ultra-short distal residue. The macroporous structure, whose size is thought to be optimal at 640 mm, facilitates interlocking between host bone and implants by providing room for newborn tissue, which is conductive to biological fixation . However3D-printed implants with the highly cancellous surface have developed biological fixation in the orthopedic area. A titanium interface with an interconnected porous structure was produced using the EBM technique, giving the requisite strength while enabling bone growth deep within the pores , 19, 38.Tissue coverage is the key to extending the life of prostheses and improving the prognosis. The medial gastrocnemius flap, being advantageous in promoting collagen deposition and tissue ingrowth along with the characteristics of versatility and malleability to fill dead space, was proposed in endoprosthetic tibia replacement to decrease infection rates , 43. ResThis case report first presents a novel limb- and joint-preserving alternative to amputation for patients with chondrosarcoma invading the entire length of the tibia and vascular bundle. The computer-assisted design, 3D-printed tibial prosthesis equipped with extracortical plates and porous contact surface, along with a dismountable plate, exhibited the excellent capacity to grasp the ultra-short residual bone of distal tibia in the short-term period. Longer follow-up is needed to verify the durability of the prosthetic and soft tissue reconstruction.


In this work, we compared the titers resulting from vaccination and tried to understand the potential factors affecting the immune response to the available SARS-CoV-2 vaccines. This study was conducted on 670 volunteers employed at the University of Pisa and undergoing a health surveillance program at the University Hospital of Pisa. For each participant, 10 mL of blood, information about contacts with confirmed cases of COVID-19, age, sex, SARS-CoV-2 vaccination status, previous SARS-CoV-2 infection and symptoms, type of vaccine and the date of administration were collected. In the multivariate analysis, the type of vaccine, the presence of symptoms in SARS-CoV-2 positive individuals, and the distance from the second dose significantly affected the antibody titer; the combined vaccination resulted in a faster decay over time compared with the other types of vaccination. No significant differences were observed between Spikevax and Comirnaty ( The SARS-CoV-2 outbreak has represented a global health issue affecting not only the general population worldwide but also many workers exposed to higher work-related risks of SARS-CoV-2 infection, for which the implementation of adequate prevention protocols is still challenging. With the development of SARS-CoV-2 vaccines, many authors started evaluating the immunization efficacy of the available vaccines mainly through sero-positivity tests or by a quantitative assessment of the IgG against the spike protein of SARS-CoV-2 virus in vaccinated subjects ,2. HowevIn Italy, the vaccination campaign against the SARS-CoV-2 virus began on 31 December 2020. Priority was initially given to health workers and to people affected by chronic diseases with a high impact on health and to older people. These categories had access to m-RNA vaccine, such as Comiranty. Afterwards, some professional categories were identified to have higher priority on vaccination than general population. These included teachers and school staff of all levels. In these categories, Vaxzevria was administered, depending on regional vaccination plan. The University of Pisa has also promoted the diffusion of vaccination among its employers.In this work, we analyzed the anti-spike antibody titer among vaccinated workers of the University of Pisa enrolled in health surveillance programs. We compared the titers resulting from different vaccination types and tried to understand the potential factors that can have affected the immune response to the available SARS-CoV-2 vaccines.This study was conducted on 670 volunteers employed at the University of Pisa and undergoing a health surveillance program at the University Hospital of Pisa and recruited between May and August 2021.Subjects were contacted through an email from the University that informed them of the possibility to attend the test and that gave them all the information on the study. They were asked to reserve a blood test around 30 days after their second dose of vaccination. As they came to have their blood sample collected, information about contacts with confirmed cases of COVID-19, age, sex, SARS-CoV-2 vaccination status, type of vaccine and the date of administration of the second dose was collected for each participant. For subjects who developed COVID-19 before completing the vaccination scheme, data about the experienced symptoms and the need for hospitalization were also collected. All subjects who reported SARS-CoV-2 infection had developed the infection before the second dose of the vaccine; consequently, in accordance with Italian law, they had only performed one vaccination dose after natural immunization. Subjects for which vaccination data were unavailable were excluded from the study.The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of Comitato Etico Regionale per la Sperimentazione Clinica della Regione Toscana Sezione: AREA VASTA NORD OVEST, Prot: COV19VACC, 31 January 2022. All participants provided the written informed consent. For each participant, 10 mL of blood was collected 30 or more days after the second dose (except for the unvaccinated subjects) to evaluate the relationship between the antibody titer and other variables. The titer of the IgG antibodies against the receptor binding domain (RBD) of the SARS-CoV-2 spike protein was determined with a chemoluminescence-based assay on the Abbott Architect platform according to the manufacturer’s instructions. All samples have been handled according to the OMS guideline for manipulating potentially infected biological samples ,5. In this prospective study, the sample size was calculated considering a greater ability of Comirnaty vaccine to produce antibodies anti SARS-CoV-2 than the Vaxzevria vaccine. Effect size (difference between Comirnaty and Vaxzevria) and standard deviation were assessed to be around 100 UA/mL and 350 UA/mL, respectively. In this condition setting power at 95% and α-error at 5% it was necessary to enroll 670 subjects.Categorical data were described by absolute and relative frequency, continuous data by median and interquartile range. To compare “anti SARS-CoV-2 antibody titer” with continuous factors  Spearman’s correlation analysis was applied. The comparison between “anti SARS-CoV-2 antibody titer” and categorical factors  was performed by Mann–Whitney test or Kruskal–Wallis test followed by multiple comparisons with Bonferroni method. All factors resulting significant to the univariate tests were analyzed together by a multiple linear regression model as multivariate analysis. Regression coefficient with 95% confidence interval, standard error, and beta value were indicated and Durbin–Watson parameter to assess autocorrelation in the residuals due to the model was also calculated. Anti SARS-CoV-2 antibody titer were also compared with symptoms, hospitalization, dyspnea, fever > 38 °C, pneumonia, headache, ageusia/anosmia and cough among the SARS-CoV-2 positive individuals using Mann–Whitney test. Significance was fixed at 5% and all analyzes were carried out with SPSS technology v.27.The study population included 670 subjects, of which 279 (41.6%) were male and 391 (58.4%) females, with a median age of 50 (IQR 41–57). Among these, three were not vaccinated, 493, 142, and 16 were vaccinated with two doses of Vaxzevria, Comirnaty, or Spikevax, respectively. For 16 subjects that received the first dose of Vaxzevria and a second dose of an mRNA-based vaccine , the vaccination type has been reported as “combined”. Nineteen participants (2.8%) developed COVID-19 before completing the vaccination scheme, thus receiving only one dose . Among the confirmed COVID-19 cases, 89.5% developed disease-related symptoms, with fever and cough being the most frequent . Only three patients (15.8%) required hospitalization.p < 0.001). Similarly, a confirmed infection of SARS-CoV-2 and the development of COVID-19 symptoms were associated with a higher antibody level . A positive correlation was observed between the antibody titer and the distance from the second dose (p = 0.045); no correlation with age was observed (p > 0.05)  . p < 0.0001). The detailed results of this comparison are reported in To evaluate how different types of vaccines affected the titer, we carried out a Bonferroni corrected pairwise comparison. Vaccination with Spikevax or a combination of Vaxzevria and an mRNA-based vaccine led to the highest antibody levels, with a median IgG AU of 12,127.5 and 7935.7, respectively. Two doses of Comirnaty resulted in significantly higher antibody levels than two doses of Vaxzevria , and the distance from the second dose significantly affected the antibody titer, as shown in Interestingly, a negative correlation emerged between the titer and the distance from the second dose.p > 0.05), while the antibody levels remain more stable in subjects undergoing Vaxzevria vaccination (p < 0.01) compared with mRNA-based vaccines (When we evaluated the relationship between the antibody titer and the distance from second dose in different types of vaccine, we found that the combined vaccination resulted in a faster decay over time compared with the other types of vaccination. No significant differences were observed between Spikevax and Comirnaty (vaccines .In this work, we reported that factors such as the type of vaccination, the development of a symptomatic SARS-CoV-2 infection and the distance from the second dose could affect the levels of the anti-spike antibodies among people vaccinated against COVID-19. Distance from second dose showed different behaviors in uni- and multivariate analysis. It is possible that the time between vaccine and testing differed according to the type of vaccine administered; correcting for the type of vaccine, the distance showed a negative correlation with the antibody titer, as would be expected. Interestingly, the occurrence of interstitial pneumonia or the need for hospitalization were associated with a higher, although not statistically significant, antibody titer. These observations are consistent with the findings of other groups showing a higher antibody titer in subjects with a symptomatic SARS-CoV-2 infection ,7,8,9,10We did not observe any significant correlation between the antibody titer and gender or age. Although this observation was consistent with the finding of other studies ,15, otheIn previous works, Dorschug et al.  and PeteWhile these observations suggest the importance of the booster dose, they do not allow establishing an antibody cut-off level to estimate an eventual loss of protection from SARS-CoV-2 infection over time. In a study conducted on Rhesus macaques, McMahan et al. reported that the adoptive transfer of purified IgG from convalescent to naïve macaques protected these latter against SARS-CoV-2 challenge in a dose-dependent manner. The authors showed that even low antibody titers were sufficient for protection against SARS-CoV-2, with cellular immune response contributing to protection when antibody responses were suboptimal . AdditioThis work has several limitations. Firstly, the serological tests were not followed by neutralization assays, which can make the interpretation of the results a bit challenging, although some data suggest a correlation between the levels of the total and neutralizing IgG . AdditioAlthough some of these data are present in the literature, our study highlighted that the type of vaccine, a SARS-CoV-2 infection, and the symptom’s severity are the most relevant factors affecting the antibody titer among people vaccinated against COVID-19. Conversely, we did not find any correlation between the titer and the age or sex. Moreover, Vaxzevria showed a lower but more stable response.The data reported in this work may contribute to highlighting the factors affecting the immune response in vaccinated subjects, however no conclusion can be drawn about the efficacy in protecting against SARS-CoV-2 infection or reducing the severity of the symptoms.Despite the fact our study represents only a small and partial step in this direction, identifying factors affecting the immune response would be crucial in the evaluation and organization of vaccination campaigns aimed at the general population, addressing the choices of vaccine schedule and of the categories of population at risk to be prioritized.


Multiple myeloma (MM) is the second most common hematological malignancy. Initially, prognosis for MM patients was poor. However, due to the development of novel treatment regimens, their clinical outcomes have significantly improved. One of the milestones in the treatment of MM was the implementation of immunomodulatory drugs (IMiDs). Lenalidomide (LEN) is probably the most commonly used IMiD worldwide. However, despite its potent anti-MM activity, the vast majority of patients become LEN-resistant. In this review, we focus on LEN-resistance mechanisms as well as on strategies for the treatment of LEN-refractory disease. Multiple myeloma (MM) is the second most common hematologic malignancy, accounting for approximately 1% of all cancers. Despite the initial poor prognosis for MM patients, their life expectancy has improved significantly with the development of novel agents. Immunomodulatory drugs (IMiDs) are widely used in MM therapy. Their implementation has been a milestone in improving the clinical outcomes of patients. The first molecule belonging to the IMiDs was thalidomide. Subsequently, its novel derivatives, lenalidomide (LEN) and pomalidomide (POM), were implemented. Almost all MM patients are exposed to LEN, which is the most commonly used IMiD. Despite the potent anti-MM activity of LEN, some patients eventually relapse and become LEN-resistant. Drug resistance is one of the greatest challenges of modern oncology and has become the main cause of cancer treatment failures. The number of patients receiving LEN is increasing, hence the problem of LEN resistance has become a great obstacle for hematologists worldwide. In this review, we intended to shed more light on the pathophysiology of LEN resistance in MM, with particular emphasis on the molecular background. Moreover, we have briefly summarized strategies to overcome LEN resistance and we have outlined future directions. Multiple myeloma (MM) is a relatively rare malignancy, accounting for approximately 10% of hematologic neoplasms and 1% of all cancers , making Several mechanisms are postulated to contribute to drug resistance in MM. For instance, it was demonstrated that multidrug resistance-1 (MDR1)/P-glycoprotein (Pgp), an ATP-dependent membrane transporter, promotes the efficient efflux of carfilzomib (CFZ) and doxorubicin in MM . MoreoveDrug resistance is one of the greatest challenges of modern oncology and has become the main reason for treatment failure in cancer. It is estimated that approximately 90% of cancer-related deaths occur as a consequence of drug resistance . ResistaLEN is an immunomodulatory derivative of THAL with more potent anti-MM activity ,15. Its Despite the potent anti-MM activity resulting in high clinical efficacy, the exact mechanism of action has not yet been determined. The central target molecule for LEN is cereblon (CRBN). CRBN interacts with DNA binding protein 1 (DDB1) and together with cullin-4A (CUL4) and regulator of cullins 1 (ROC1) to form the CRL4 E3 ubiquitin ligase complex (CRL4), which triggers an increase in ubiquitination and subsequent degradation of the two transcription factors Ikaros (IKZF1) and Aiolos (IKZF3)  25]. IK. IK25]. IMiDs are derivatives of THAL. Therefore, they exhibit a similar mechanism of action, i.e., binding to CRBN elicits their downstream activity, overlapping toxicity profile, as well as shares some adverse reactions. In addition, all molecules have a similar chemical structure. However, there are subtle but important differences between these three agents. All three representatives of IMiDs have a mutual phthalimide and glutarimide carbon skeleton and are distinguished only by the side chain; more precisely, by the carboxyl and amino groups  25]. . 25]. LEN was proved to be a highly effective anti-MM agent. Nevertheless, over time, MM cells exposed to the drug can evade its target pathways and become resistant to therapy. As mentioned above, the LEN mechanism of action is complex and not entirely elucidated. In addition, it exhibits numerous pleiotropic effects. It can therefore be hypothesized that the molecular mechanisms developed in order to select a resistant clone are at least as complex as the mechanism of action itself. The resistance mechanisms are summarized in Fbxo7 E3 ligase-related decay of CRBN. On the other hand, the absence of CSN9 signalosome activity induces the SCFFbxo7 complex and promotes CRBN degradation and mediates resistance to immunomodulatory drugs including LEN [CRBN is the main target molecule for LEN, and triggered downstream mechanisms elicit the vast majority of the pharmacological effects and are responsible for its anti-MM properties . Therefoding LEN . Similarding LEN ,44. The ding LEN . Nonetheding LEN ,44. As sding LEN . On top of CRBN downregulation, mutations in the CRBN itself or the CRBN pathway appear to mediate LEN resistance. Kortüm and colleagues conducted a study where they performed targeted sequencing to screen 50 multidrug refractory MM patients. Their analysis showed that mutations in the CRBN or IMiD binding site of CRBN appeared to induce LEN resistance. In addition, the longitudinal evaluation of three individuals with CRBN mutations at the onset of IMiD resistance confirmed that these mutations were not detectable before, when they had been sensitive to either LEN or POM . GoodingBarrio et al. demonstrated that on top of mutations in a gene encoding CRBN at the LEN/POM binding site, other point mutations appeared to play a role in the pathogenesis of LEN/POM resistance in the following manner. They either hindered interactions with other molecules of the complex, or those mutations could destabilize the complex’s effect exerted on its molecular targets. As well as CRBN mutations, point mutations in the genes encoding the CRL4 ligase complex are also involved in the pathogenesis of LEN resistance. Only IKZF1/3 mutations affecting the lenalidomide/cereblon binding site confer LEN-resistance. While alterations in Aiolos, which were possible to detect at the time of diagnosis, appear to contribute the pathogenesis of MM itself rather than to the clinical resistance induced by the long-lasting exposure to the drugs . In an iCRBN-induced ubiquitylation of target proteins, and this intercepted their intracellular degradation in a proteasome. This also applies to the LEN-induced decay of Ikaros and Aiolos. Furthermore, the depletion of USP15 enhances LEN-mediated degradation of IKZF1/3 in refractory MM cell lines [Tagging a protein with ubiquitin requires three groups of enzymes which are known as E1, E2 and E3. They act cooperatively to ubiquitinate the target protein. LEN interacts with E3 and CRBN forming the CRL4 E3 ligase complex. Nevertheless, Lu et al. demonstrated, using the CRISPR-Cas9 screening approach, that one of the E2 enzymes’, UBE2G1, protein downregulation, gene deletion or mutation confers resistance to both LEN and POM in human myeloma cell lines and may lead to reduced CRL4 CRBN activity. Nonetheless, these MM cells remained sensitive to the more potent IKZF1/3 degrader CC-220. In conclusion, it will be of fundamental importance to investigate whether loss of UBE2G1 activity is associated with clinical resistance in patients not responding to LEN. Moreover, the results imply that the development of novel IMiDs could be of paramount importance, as UBE2G1-depleted cells remained sensitive to a more potent CRBN modulator such as CC-20 . As mentll lines . In addition to the abovementioned mechanisms, it can be hypothesized that epigenetic alterations play a role in the development of LEN resistance. Dimopoulos et al. investigated the mechanisms of LEN resistance using an in vitro model. Their results revealed that LEN-resistant MM cells showed downregulation of CRBN. they then investigated if epigenetic alterations contribute to the development of LEN resistance and CRBN downregulation. Interestingly, they observed that the promoter region of CRBN was not silenced and that the CRBN expression was not under the influence of epigenetic alterations, such as DNA methylation, but possibly by other cis or trans regulatory mechanisms. However, methylation changes did play a role. They established that IMiD-resistance was associated with thorough epigenetic modifications which included changes in chromatin accessibility and DNA methylation. Nevertheless, it was also highlighted that reprogramming did not directly interact with the main components of CRBN-related pathway. Moreover, sensitivity to LEN can be restored with a combination of 5-azacytidine and EPZ-6438 yet in a CRBN-independent manner . On the In addition to direct changes in DNA methylation, there are other epigenetic mechanisms contributing to the development of LEN resistance. However, some of them may also be associated with methylation alterations. Of particular relevance are non-coding RNAs that mediate the loss of LEN sensitivity in a variety of ways. Jakobsen et al. investigated the role of circular RNAs (circRNAs) in the mechanisms underlying the development of resistance to IMiDs, including LEN, in an in vitro model. Most notably, they established that genome-wide circRNA expression represented a good response to IMiD, and alterations in its patterns occurred when the IMiDs-refractory state was achieved. It was determined that ciRS-7 was the most depleted circRNA in LEN-refractory MM cell line. The loss of ciRS-7 was evidently associated with the enhanced methylation of the CpG island in the promoter region of its own gene, named LINC00632. The expression level of both molecules, LINC00632 and ciRS-7, was restored to some degree by the treatment of a combination of an EZH2 inhibitor (EPZ-6438) and 5-azacytidine (DNA methyltransferase inhibitor). Interestingly, after such exposure, cells regained the sensitivity. However, a subsequent analysis revealed that ciRS-7 did not appear to be directly involved in the pathogenesis of LEN-resistance development. Nevertheless, alterations in genome-wide circRNA expression patterns are associated with acquired resistance to IMiDs and should be further investigated . Another in vitro study by Caracciolo and co-workers yielded interesting results. miR-22 has been found to be associated with LEN sensitivity. Low miR-22 levels were bound to LEN resistance and a poor response to LEN. On the contrary, upregulation of miR-22 correlated with drug sensitivity, predominantly through downregulation of MYC. Furthermore, the study depicted that miR-22 potentiates NK-mediated cytotoxicity induced by LEN. Interestingly, miR-22 overexpression restored LEN sensitivity in MM cell lines with a drug-resistant phenotype. Taken together, these data indicate that miR-22-induced downregulation of MYC is able to potentiate both direct LEN- and NK-mediated cytotoxicity in MM cells . Despite emerging evidence that epigenetic mechanisms play an important role in the pathogenesis of the development of LEN resistance, little is still known due to the complexity of the interactions involved. It was established that DNA methylation, as well as non-coding RNA such as miRNA and circRNAs, at least partially explain this phenomenon. Further research in this area is of paramount importance due to the potential reversibility of epigenetic alterations and, thus, clinical utility for relapsed and refractory multiple myeloma (RRMM) patients. The expression pattern of particular clusters of differentiation (CD) or other surface antigens appears to be associated with LEN resistance or diminished drug sensitivity. For instance, Kawano and colleagues investigated the expression of CD138 in MM cells and the resultant clinical implications. The obtained results showed that decreased expression of CD138 was associated with the immature phenotype of MM cells and poor prognosis, even in a subpopulation of patients treated with high-dose chemotherapy. Moreover, it was bound with refractoriness to LEN. The underlying mechanisms were complex and not entirely elucidated. Nonetheless, the authors hypothesized that the observed downregulation of interferon regulatory factor 4 (IRF4) may at least partially explain reduced LEN sensitivity . On the Glucose-regulated protein (GRP) 78 belongs to the heat shock protein (HSP) 70 family with chaperone activity. Rasche et al. demonstrated that there is a variation in GRP78 expression on the cellular surface starting from monoclonal gammopathy of undetermined significance (MGUS) to advanced relapsed and refractory to BTZ and LEN MM. The more advanced the MM, the greater the expression of GRP78, including LEN-resistant MM cells. Interestingly, the combined treatment of LEN and PAT-SM6  exhibited synergistic effects and restored LEN sensitivity in previously resistant cells. Moreover, a 62-year-old man with triple refractory MM was treated with PAT-SM6, BTZ, and LEN achieved partial remission of both intra- and extramedullary lesions . FergusoThe Wnt/β-catenin pathway is vital in both embryonic development and in the maintenance of proper function of mature tissues. Once activated, the typical Wnt pathway stabilizes the β-catenin and moves it into the nucleus. This promotes the upregulation of various genes which control multiple cellular pathways and processes including cell proliferation, survival, differentiation and migration . What isThere are also other mechanisms contributing to the development of LEN resistance that cannot be assigned to the abovementioned categories, but which may be important for future study design. Therefore, we believe that these studies are worth including and briefly summarized in our review.Cyclin-dependent kinase 6 (CDK6) is a vital protein for the proper regulation of the cell cycle. It was demonstrated by Ng and team that the upregulation of CDK6 decreased the sensitivity of MM cells to LEN, which contributes to the development of resistance. In addition, the study depicted that inhibition or degradation of CDK6 was highly synergistic with immunomodulatory drugs and potentiates its anti-MM effects. It was concluded that CDK6 upregulation is a drug-susceptible target in IMiD-resistant MM .Mori and colleagues demonstrated a novel mechanism for the development of multidrug resistance in MM, including refractoriness to LEN. In the first place, they determined that high MYC expression correlates with low nuclear receptor co-repressors 2 (NCOR2) expression, which belongs to nuclear receptor co-repressors that activate histone deacetylase and alter epigenomic modification. Thereafter, they established a LEN-resistant MM cell line. A subsequent analysis showed that long-term IMiD treatment induced NCOR2 mutation and NCOR2 downregulation. Next, they tested LEN- and POM-resistant cell lines with CPI0203 /ACY1215 (histone deacetylase 6 inhibitor). Both cell lines showed significant resistance to both agents, suggesting that MYC upregulation contributes to multidrug resistance .The termOcio et al. conducted a very interesting in vivo study where they established a xenograft model resistant to LEN plus DXM and POM plus DXM. First, the results of the study showed no cross-resistance between IMiDs. Subsequently, it was demonstrated that mice, which had become refractory first to one treatment regimen and subsequently to the next, were re-treated with the initial regimen (either RD or PD) after a wash-out period without treatment. Interestingly, the tumors again responded to treatments to which they had initially developed resistance. In conclusion, the results revealed an upregulation of the MEK/ERK pathway in acquired LEN and POM resistance. Interestingly, the addition of a MEK inhibitor reversed IMiD resistance in both in vitro and in vivo models . In anot+ cells from MM individuals, and that exogenous IL-6 upregulated HO-1 in malignant plasma cells. IL-6-induced high expression of HO-1 allowed MM cells to resist LEN. This was hypothetically attributed to the IL-6-mediated activation of the JAK/STAT3 pathway. However, diminishing the expression of IL-6 mediated by HO-1 re-sensitized MM cells to LEN [Wang and co-workers demonstrated that downregulation of the chemokine CCL20 was associated with LEN resistance, and the addition of CCL20 restored LEN sensitivity in both in vitro and xenograft models . Anothers to LEN . Colombos to LEN . Yamamoto et al. demonstrated another molecular and cellular mechanisms of LEN resistance in MM. In comparison to LEN-sensitive MM cells, cells that exhibited the resistant phenotype were characterized by the increased secretion of extracellular vesicles (EV) and elevated adherence abilities. A whole transcriptome analysis revealed that the Sortilin 1 (SORT1) and Lysosomal Associated Membrane Protein 2 (LAMP2) genes were core regulatory genes of EV secretion. In addition, their knockout resulted in lowering EV secretion and the loss of adhesive properties of resistant cells, eventually leading to greater LEN sensitivity . SimilarCCAAT/enhancer-binding protein-β (C/EBPβ) is one of crucial regulators of growth and differentiation of B cells. IMiD compounds, LEN and POM downregulate eIF4E, which prevents the translation of C/EBPβ and, as a result, inhibits IRF4 transcription. This in turn decreases the expression of the network of IRF4-dependent transcription factors, eventually leading to the inhibition of MM proliferation. On the other hand, the overexpression of C/EBPβ mediates IMiD resistance, emphasizing the role of C/EBPβ in promoting resistance to LEN and POM .It appears that low CRBN expression, mutations in CRBN and in genes encoding downstream proteins collectively contribute to the development of LEN resistance. Nevertheless, alterations in CRBN itself or its downregulation seem to be the principal component. This was demonstrated in a study by Zhu and colleagues, which depicted that CRBN depletion and mutations should be considered as the most prevalent mediators of acquired resistance to IMiDs in MM. Furthermore, they also described a new mechanism of resistance driven by a proinflammatory cytokine—IL-6 and the activation of STAT3 . Therefore, modulation or restoration of CRBN signaling appears to be a viable research direction with potential clinical implications. Hansen and colleagues conducted an interesting in vitro study where they investigated possible options to overcome LEN resistance. The obtained results showed that LEN sensitivity can be restored despite low intracellular LEN levels, as in the H929 R10-1 MM cell line. They described a CRBN E3 ligase modulator named CC-92480, a molecule acting as though it was a molecular glue, facilitating the interplay between IKZF1 and CRBN and promoting targeted docking to the CRL4-CRBN E3 complex. CC-92480-dependent attachment of IKZF1/3 to CRBN results in polyubiquitination and eventually proteasome-mediated decay of a protein, which results in the subsequent apoptosis of LEN-resistant MM cells . LEN is a potent anti-MM drug. Nevertheless, despite its high clinical efficacy, there is a patient population that has become resistant to LEN. Therefore, the development of novel molecules, the implementation of different treatment regimens, as well as basic research in this field are of great importance. There is ample evidence that cross-resistance within immunomodulatory drug class does not exist. In the first place, LEN was proved to be effective in THAL-resistant patients . SubsequAs well as novel agents which are currently being investigated in clinical trials, the development of alternative treatment regimens consisting of already existing drugs should be considered and explored. Unconventional modification can lead to a good clinical response. Furthermore, in the vast majority of cases it is an efficient and cost-effective option that can be quickly implemented. Ghosh at al. conducted a retrospective study in which they analyzed 24 patients treated with LEN and DXM (Rd). After confirming disease progression to Rd, clarithromycin was added to Rd treatment regimen which remained unchanged in terms of dosage. The overall beneficial response rate  was relatively high—45.8% . A survival analysis revealed that the median PFS was demonstrated to be 4 months and 25 months of median OS with the median follow-up of 27.5 months. Of particular interest, high-risk cytogenetics (FISH) had no significant negative impact on PFS, but adversely affected OS, indicating a poor response of these patients to further treatment. The study concluded that the addition of clarithromycin to LEN and DXM could overcome resistance to LEN and DXM and lead to durable clinical responses . 2 with Rd in RRMM and implied that AZA might be putatively beneficial in an attempt to face the LEN/POM refractoriness, presumably via activating differentiation pathways. The relatively low response rates and the relation of the satisfactory clinical outcome with low plasma levels of the AZA inactivating enzyme named CDA imply that the AZA-based regimen will require further adjustments. Moreover, a careful patient inclusion criteria may be essential to maximize clinical outcomes [Kalff et al. conducted a clinical trial where they examined the efficacy of oral azacytidine (AZA) in LEN-resistant MM. They showed that in a group of previously heavily treated LEN-resistant, RRMM patients, meaningful clinical responses were achieved without significant toxicity when treated with AZA in combination with the Rd regimen. Interestingly, proteomic analysis revealed that higher CRBN protein expression in MM cells before treatment correlated with superior outcomes . Howeveroutcomes . Additionally, cyclophosphamide (CTX) has the ability to overcome LEN resistance. Alahmadi and team showed that CTX added to the Rd regimen at the time of diagnosis of disease progression is clinically beneficial. The obtained results revealed that the overall response rate at the level of at least PR  was 34%, and clinical benefit (at least stable disease) was observed in the vast majority of enrolled individuals 87%). The median length of therapy with the regimen Rd + CTX was 6.9 months. The median PFS was 6.1 months from the addition of CTX and 24.1 months from the start of Rd %. The me. SimilarThe abovementioned alterations and modifications of well-established treatment regimens are not an alternative to novel agents with more potent anti-MM activity. However, they can be considered an easily accessible and cost-effective option in regions and institutions where new anti-MM drugs are, due to various reasons, difficult to obtain. Daratumumab is an anti-CD38 antibody that exhibits anti-MM activity through various mechanisms. The combination of daratumumab (DARA), BTZ and DXM in RRMM was investigated and compared to a regimen consisting of BTZ and DXM solely. The combination tested in the study arm was found to be more effective against RRMM, including the LEN-resistant subset of patients . AnotherCarfilzomib (CFZ) is a proteasome inhibitor which is a derivative of BTZ. The ENDEAVOUR clinical trial established that the combination of CFZ and DXM is a superior therapeutic option than BTZ and DXM. Importantly, the investigated treatment regimen was found to be effective in LEN-resistant MM . SimilarInhibition of the JAK-STAT pathway may be an interesting novel therapeutic approach. This pathway contributes to the development and progression of MM among others due to interaction with BM microenvironment. For instance, macrophages have the ability to differentiate into either M1 (anti-cancer activity and production of inflammatory cytokines) or M2 . Chen and colleagues conducted an interesting study where they demonstrated in a preclinical model of MM that inhibition of the JAK pathway suppresses M2 polarization. In addition, they showed that ruxolitinib (an inhibitor of the JAK pathway) can overcome LEN resistance . FurtherLEN resistance appears to be mediated predominantly through alterations in CRBN-mediated signaling. Nevertheless, other mechanisms also contribute to this phenomenon. Identifying the molecular pathways underlying LEN resistance is of a paramount importance. First of all, because they may emerge in the future as potential therapeutic strategies and become the subject of translational research, and consequently improve patients’ outcomes. Moreover, many new therapeutic strategies are available for the successful treatment of LEN-resistant MM. Of particular importance are monoclonal antibodies and novel derivatives of currently used antiMM agents. At the same time, drugs widely used in other diseases, such as JAK-STAT pathway inhibitors, should be investigated in MM, especially when their mechanism of action may interfere with pathophysiological pathways involved in the development and progression of MM.


Background: The COVID-19 mRNA vaccine was granted emergency use authorization (EUA) on December 18, 2020. Some patients experienced a transient, pruritic rash at the injection site, which was referred to as “COVID arm”. It is considered a delayed-type hypersensitivity reaction and occurs mostly in individuals after vaccination with the Moderna vaccine but rarely with other mRNA vaccines. Case Summary: A healthy 33-year-old woman with no history of disease or long-term medication presented with fever and rash on the left upper arm three days after her first vaccination with the mRNA-1273 vaccine (Moderna). Results: After treatment with antihistamines, all lesions gradually resolved over the following 4 to 5 days. Conclusion: We report a case of “COVID arm”: a localized erythematous rash surrounding the injection site that arose three days after the first dose of the Moderna COVID-19 vaccine. Delayed injection site reactions occurred in approximately 0.8% of vaccinated people after the first dose and in approximately 0.2% after the second dose. The lesions persisted for several days and then resolved without treatment. Health care providers were not prepared to address these delayed local reactions to the mRNA-1273 vaccine. Given the scale-up of mass vaccination campaigns worldwide, these skin reactions may likely generate concerns among patients and requests for evaluation. Although these skin reactions have not been consistently recognized, guidance regarding the second dose of the vaccine has varied, and many patients have unnecessarily received antibiotic agents. A novel coronavirus was identified at the end of 2019 as the cause of a cluster of pneumonia cases in Wuhan, China. It spread rapidly throughout China and the world in a few months. Coronavirus is a member of the family Coronaviridae. “Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)” as the name for the new virus was announced by International Committee on Taxonomy of Viruses (ICTV), in order to differentiate from the coronavirus responsible for the SARS outbreak of 2003 ,5,6. ImmThe majority of reported allergic reactions to mRNA COVID-19 vaccines occurred within 30 min of vaccination (mostly within 15 min) . “COVID The patient was a healthy 33-year-old woman with no history of systemic disease, allergies, or long-term medication. Her family history was unremarkable. She was admitted to the emergency department and presented a pruritic rash on the left upper arm , and fevDelayed injection site reactions are currently considered delayed-type (Type IV) or T-cell-mediated hypersensitivity, supported by a skin biopsy of one of the late local reactions , althougThe onset of delayed skin reactions usually begins approximately 3 days after vaccination, while one observational cohort study reported the occurrence 3–9 days (median 7) after the first dose of mRNA-1273 . JacobsoIn summary, current clinical data suggest that potential recipients of the mRNA-1273 vaccine can be reassured that delayed injection site skin reactions are benign, self-limited adverse events that resolve gradually and do not lead to serious clinical problems. It is important for public health agencies to educate the public about the possibility of these delayed injection site reactions to the mRNA-1273 vaccine and reassure them. Nevertheless, more evidence is needed to characterize the epidemiology, mechanism, prevention, treatment, and why delayed injection site reactions seems to occur more frequently in females than males, even among different races.We reported a case of a delayed skin injection site reaction to the mRNA-1273 vaccine. The comprehensive mechanism is not well known, and the clinical characteristics are consistent with delayed-type hypersensitivity.