Background - COVID-19 has led to over 1 million deaths worldwide and has been associated with cardiac complications including cardiac arrhythmias. The incidence and pathophysiology of these manifestations remain elusive. In this worldwide survey of patients hospitalized with COVID-19 who developed cardiac arrhythmias, we describe clinical characteristics associated with various arrhythmias, as well as global differences in modulations of routine electrophysiology practice during the pandemic. Methods - We conducted a retrospective analysis of patients hospitalized with COVID-19 infection worldwide with and without incident cardiac arrhythmias. Patients with documented atrial fibrillation (AF), atrial flutter (AFL), supraventricular tachycardia (SVT), non-sustained or sustained ventricular tachycardia (VT), ventricular fibrillation (VF), atrioventricular block (AVB), or marked sinus bradycardia (HR<40bpm) were classified as having arrhythmia. De-identified data was provided by each institution and analyzed. Results - Data was collected for 4,526 patients across 4 continents and 12 countries, 827 of whom had an arrhythmia. Cardiac comorbidities were common in patients with arrhythmia: 69% had hypertension, 42% diabetes mellitus, 30% had heart failure and 24% coronary artery disease. Most had no prior history of arrhythmia. Of those who did develop an arrhythmia, the majority (81.8%) developed atrial arrhythmias, 20.7% developed ventricular arrhythmias, and 22.6% had bradyarrhythmia. Regional differences suggested a lower incidence of AF in Asia compared to other continents (34% vs. 63%). Most patients in in North America and Europe received hydroxychloroquine, though the frequency of hydroxychloroquine therapy was constant across arrhythmia types. Forty-three percent of patients who developed arrhythmia were mechanically ventilated and 51% survived to hospital discharge. Many institutions reported drastic decreases in electrophysiology procedures performed. Conclusions - Cardiac arrhythmias are common and associated with high morbidity and mortality among patients hospitalized with COVID-19 infection. There were significant regional variations in the types of arrhythmias and treatment approaches.

In recent years miscellaneous smart micro/nanosystems that respond to various exogenous/endogenous stimuli including temperature, magnetic/electric field, mechanical force, ultrasound/light irradiation, redox potentials, and biomolecule concentration have been developed for targeted delivery and release of encapsulated therapeutic agents such as drugs, genes, proteins, and metal ions specifically at their required site of action. Owing to physiological differences between malignant and normal cells, or between tumors and normal tissues, pH-sensitive nanosystems represent promising smart delivery vehicles for transport and delivery of anticancer agents. Furthermore, pH-sensitive systems possess applications in delivery of metal ions and biomolecules such as proteins, insulin, etc., as well as co-delivery of cargos, dual pH-sensitive nanocarriers, dual/multi stimuli-responsive nanosystems, and even in the search for new solutions for therapy of diseases such as Alzheimer’s. In order to design an optimized system, it is necessary to understand the various pH-responsive micro/nanoparticles and the different mechanisms of pH-sensitive drug release. This should be accompanied by an assessment of the theoretical and practical challenges in the design and use of these carriers.

The successful treatment of bone infections is a major challenge in the field of orthopedics. There are some common methods for treating bone infections, including systemic antibiotic administration, local nondegradable drug vehicles, and surgical debridement, and each of these approaches has advantages and disadvantages. In the present study, the antibiotic vancomycin (VANCO) was loaded in silk fibroin nanoparticles (SFNPs) and the complexes were then entrapped in silk scaffolds to form sustained drug delivery systems. The release kinetics of VANCO from SFNPs alone and when the SFNPs were entrapped in silk scaffolds were assessed at two different pH values, 4.5 and 7.4, that affected the release profiles of VANCO. Disk diffusion tests performed with pathogens causing osteomyelitis methicillin-resistant Staphylococcus aureus (MRSA) showed antibacterial activity of the released drug at two different pH values. Additionally, injection of 8 × 10 CFU MRSA in rat's tibia induced severe osteomyelitis disease. Radiographic and histopathological analyses were performed to evaluate the effectiveness of treatment after 6 weeks. The VANCO-loaded silk fibroin nanoparticles entrapped in scaffolds reduced bone infections at the defected site with better outcomes than the other treatment groups. In conclusion, the delivery system with good biocompatibility and sustained release properties would be appropriate for further study in the context of osteomyelitis disease.

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Objective Based on the epidemiologic findings of Covid-19 incidence; illness and mortality seem to be associated with metabolic risk factors. This systematic review and meta-analysis aimed to assess the association of metabolic risk factors and risk of Covid-19. Methods This study was designed according to PRISMA guidelines. Two independent researchers searched for the relevant studies using PubMed, Web of Science, Cochrane Library, and Scopus. The search terms developed focusing on two main roots of “Covid-19” and “metabolic risk factors”. All relevant observational, analytical studies, review articles, and a meta-analysis on the adult population were included in this meta-analysis. Meta-analysis was performed using the random effect model for pooling proportions to address heterogeneity among studies. Data were analyzed using STATA package version 11.2, (StataCorp, USA). Results Through a comprehensive systematic search in the targeted databases we found 1124 papers, after running the proses of refining, 13 studies were included in the present meta-analysis. The pooled prevalence of obesity in Covid-19 patients was 29% (95% CI: 14–47%). For Diabetes and Hypertension, these were 22% (95% CI: 12% 33%) and 32% (95% CI: 12% 56%), respectively. There was significant heterogeneity in the estimates of the three pooled prevalence without any significant small-study effects. Such warning points, to some extent, guide physicians and clinicians to better understand the importance of controlling co-morbid risk factors in prioritizing resource allocation and interventions. Conclusion The meta-analysis showed that hypertension is more prevalent than obesity and diabetes in patients with Covid-19 disease. The prevalence of co-morbid metabolic risk factors must be adopted for better management and priority settings of public health vaccination and other required interventions. The results may help to improve services delivery in COVID-19 patients, while helping to develop better policies for prevention and response to COVID-19 and its critical outcomes.

Background and aimIt is very important to know the risk factors of coronary artery disease and the role of inflammatory markers. One of these markers is hs-CRP that has been indicated to increase in patients with coronary artery atherosclerosis. The main objective of this study was to determine the relationship between serum levels of hs-CRP and coronary lesion severity.MethodsIn the current study, we evaluated the role of hs-CRP in coronary artery disease and measured the relationship between serum hs-CRP levels and the severity of coronary lesions in 102 patients who referred to Imam Khomeini Hospital, Iran. The number of involved coronary arteries was measured. The severity of coronary lesions was evaluated by Gensini scoring method and the association between severity of coronary artery lesions and serum hs-CRP levels and other risk factors were examined.ResultsNo significant difference was found between the two groups in terms of gender. Severity of lesions had no significant difference according to Gensini score in women compared with men. Mean Gensini score was significant between the two groups (66.79±48.12 in hs-CRP positive group versus 21.09±26.25 in negative ones, p<0.05). In addition, diabetic patients were significantly more in hs-CRP positive group than negative hs-CRP group (P<0.05). In terms of smoking, there was a significant difference between the two groups. Percentage of patients with hypercholesterolemia was significantly higher in hs-CRP negative group. There was a significant difference in severity of lesions between smokers and non-smokers.ConclusionNo significant correlation was observed between serum levels of hs-CRP and severity and angiographic extent on coronary arteries in our study. Considering the potential risk of coronary inflammatory process as a new variable, it can help discover new cases of coronary lesions and follow-up and control of the selected cases.

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